METHOD FOR ESTIMATING TIME ELAPSED BETWEEN USER
SELECTION AND FIRST BIT RECEIPT FROM A SERVER
FIELD
The present invention relates to a network monitoring device
and methods for estimating time elapsed between a user's first selection
of an item or hyperlink on a web browser of a user device and a first bit
received by the user device from a corresponding web server.
BACKGROUND
[0002] Currently, solution providers have proposed deployment of
network monitoring devices to sniff packets on traffic flows of
15 communication networks and perform analysis based on the sniffed·
packets. In existing proposals, the network monitoring device (NPM)
usually has the following functions: (1) receiving packets from directional
traffic flows on transmission links in a data network; (2) performing
statistical data calculations on the received packets of traffic flows; (3)
20 reporting calculated statistical data to external processing devices or
systems, such as a customer experience management systems or a data
analytics processing device. However, there are issues associated with
these proposals which are explained below.
25 [0003] Although the NPM is intended to sniff and analyse packets in
order to acquire statistical data of user traffic, communication network
operators or data network operators are interested in knowing how end
users (customers) of their networks perceive throughput (download
throughput and/or upload throughput). For example, communication
30 network operators or data network operators are eager to determine the
time taken from a first click by the end user on a browser of the end
2
user's smartphone until a first bit (or a first byte) is received from the
corresponding server (via the operator network).
[0004] More particularly, wireless network operators may be
5 interested to know how long it takes from the first selection of a webpage
object (e.g., a universal resource locator (URL) or a hyperlink) on a
browser on a smartphone by an end user (customer) until a first bit (or a
first byte) is received from corresponding server (via the operator
network). Such time can be considered as user-perceived delay for
10 smartphone or smart device applications in which information is
requested from a server in Internet. For example, in a wireless
communication network a user-perceived delay may be caused by
several sources, such as wireless network delay while the request
message travels to a wireless network gateway connected to Internet;
15 Internet and other network delay while the request message travels to a
corresponding server responsible for processing the request; processing
time at the server while the requested information is retrieved by the
server and transmitted to the user device in a response message;
another Internet and other network delay while the response message
20 travels back to the wireless network gateway from the corresponding
server; another wireless network delay while the response message
travels to the user device from the wireless network gateway, etc.
[0005] Due to the large number of smart devices and wireless
25 communication devices continuously accessing the Internet, it is difficult
to monitor the user-perceived delay on each device .
[0006] . Against this background there is a need for a method, an
apparatus or a system to efficiently and more accurately estimate time
30 elapsed between a user's first selection on an item or hyperlink on a web
3
5
browser in a user device under control of the user and a first bit received
by the user device from a corresponding web server.
SUMMARY
[0007] According to an exemplary embodiment of the present
disclosure, there is provided a method for estimating time elapsed .
between a user's first selection on a web browser of a user device under
control of the user to a first bit received by the user device from a
10 corresponding web server comprising:
calculating, by a network monitoring device, a first delay
parameter based upon time elapsed between detections of a first request
message and a first response message, wherein the first request
message corresponds to the user's first selection on the web browser
15 • and the first response message is transmitted by the corresponding web
server in response to the first request message received by the
corresponding web server;
calculating, by the network monitoring device, a second
delay parameter based upon time elapsed between detection of the first
20 response message and a second request message, wherein the second
request message is transmitted by the user device in response to the first
response message received by the user device;
calculating, by the network monitoring device, a third delay
parameter based upon time elapsed between detection of the second
25 request message and a second response message which is transmitted
by the corresponding web server in response to the second request
message received by the corresponding web server; and
estimating the time elapsed between the user's first selection
on the web browser in the user device under control of the user to the
30 first bit received by the user device from the corresponding web server in
4
accordance with the first delay parameter, the second delay parameter
and the third delay parameter.
[0008] The step of estimating the time elapsed between the user's
5 first selection on the web browser in the user device under control of the
user to the first bit received by the user device from a corresponding web
server may comprise:
estimating the time elapsed between the user's first selection
on the web browser in the user device under control of the user to the
10 first bit received by the user device from a corresponding web server by
adding the first delay parameter, twice the second delay parameter and
the third delay parameter.
[0009] The step of calculating the first delay parameter may
15 comprise:
monitoring, by the network monitoring device, one network
equipment in a network for receipt of the first request message
corresponding to the user's first selection on the web browser;
monitoring, by the network monitoring device, another
20 network equipment in the network for receipt of the first response
message, wherein the first response message is an acknowledgement
message transmitted by the corresponding web server in response to
receipt of the first request message;
calculating, by the network monitoring device, a first delay
25 parameter based upon time elapsed between detection of the first
request message and the first response message.
30
[0010]
comprise:
The step of calculating the second delay parameter may
monitoring, by the network monitoring device, the network
equipment in the network for receipt of the second request message;
5
5 calculating, by the network monitoring device, the second
delay parameter based upon time elapsed between detection of the first
response message and the second request message.
[0011] The step of calculating the third delay parameter may
10 comprise:
monitoring, by the network monitoring device, the another
network equipment in the network for receipt of the second response
message;
calculating, by the network monitoring device, a third delay
15 parameter based upon time elapsed between detection of the second
request message and the second response message.
20
25
[0012] The first request message may correspond to a transport
control protocol (TCP) synchronization packet.
[0013] The first response message may correspond to an
acknowledgement message at TCP layer transmitted by the
corresponding web server in response to the first request message
received by the corresponding web server.
[0014] The second request message may correspond to a
Hypertext Transfer Protocol (HTTP) GET Request message.
[0015] The second response message may correspond to a
30 Hypertext Transfer Protocol (HTTP) GET Response message, and the
second response message may carry the first bit which is received by the
user device.
[0016] The method may further comprise outputting, by the network
35 monitoring device, to an external processing device the estimated time
6
i
'
5 elapsed between the user's first selection on the web browser in the user
device under control of the user to the first bit received by the user
device from the corresponding web server.
[0017] According to another exemplary embodiment of the present
10 invention, there is also provided another method for estimating time
elapsed between a user's first selection on a web browser in a user
device under control of the user to a first bit received by the user device
from a corresponding web server comprising:
monitoring, by a network monitoring device, one network
15 equipment in a network for receipt of a first request message
corresponding to the user's first selection on the web browser;
monitoring, by the network monitoring device, another
network equipment in the network for receipt of a first response message
which is transmitted by the corresponding web server in response to the
20 first request message;
monitoring, by the network monitoring device, the network
equipment in the network for receipt of a second request message, which
is transmitted by the user device in response to receipt of the first
response message;
25 mo(litoring, by the network monitoring device, the another
network equipment in the network for receipt of a second response
message which is transmitted by the corresponding web server in
response to the second request message;
calculating, by a network monitoring device, a first delay
30 parameter 01, wherein the first delay parameter 01 is time elapsed
between detections of the first request message and the first response
message;
calculating, by the network monitoring device, a second
delay parameter 02, wherein the second delay parameter 02 is time
7
5 elapsed between detections of the first response message and the
second request message;
calculating, by the network monitoring device, a third delay
parameter 03, wherein the third delay parameter 03 is time elapsed
between detections of the second request message and the second
10 request message; and
15
estimating the time, 05, elapsed between the user's first
selection on the web browser in the user device under control of the user
to the first bit received by the user device from the corresponding web
server according to an expression (1):
D5 = D1 + D2 x 2 + D3 ... expression (1).
[0018) According to another exemplary embodiment of the present
invention, there is provided a network monitoring device for estimating
20 time elapsed between a user's first selection on a web browser in a user
device under control of the user to a first bit received by the user device
from a corresponding web server comprising:
a datagram monitor configured to monitor at least two .
network devices in a network for detecting messages;
25 a metrics calculator connected to the datagram monitor and
configured to:
calculate a first delay parameter based upon time elapsed
between detection of a first request message and a first response
message, wherein the first request message corresponds to the user's
30 first selection on the web browser and the first acknowledgement
message is transmitted by the corresponding web server in response to
the first request message received by the corresponding web server;
calculate a second delay parameter based upon time
elapsed between detection of the first response message and a second
35 request message, wherein the second request message is transmitted by
8
j
5 the user device in response to the first response message received by
the user device;
calculate a third delay parameter based upon time elapsed
between detection of the second request message and a second
response message which is transmitted by the corresponding web server
10 in response to the second request message received by the
corresponding web server; and
estimate the time elapsed between the user's first selection
on the web browser in the user device under control of the user to the
first bit received by the user device from the corresponding web server in
15 accordance with the first delay parameter, the second delay parameter
and the third delay parameter.
The metrics calculator may be further configured to:
estimate the time elapsed between the user's first selection
on the web browser in the user device under control of the user to the
20 first bit received by the user device from a corresponding web server by
adding the first delay parameter, twice the second delay parameter and
the third delay parameter.
25
[0019] The datagram monitor may be further configured to:
monitor one network equipment in a network for receipt of
the first request message corresponding to the user's first selection on
the web browser;
monitor another network equipment in the network for receipt
of the first response message, wherein the first response message is an
30 acknowledgement message transmitted by the corresponding web server
in response to receipt of the request message, and
35
the metrics calculator may be further configured to calculate
a first delay parameter based upon time elapsed between detection of
the first request message and the first response message.
9
5 [0020] The datagram monitor may be further configured to monitor
the network equipment in the network for receipt of the second request
message; and
the metrics calculator is further configured to calculate the
second delay parameter based upon time elapsed between detection of
10 the first response message and the second request message.
[0021] The datagram monitor may be further configured to monitor
the other network equipment in the network for receipt of the second
response message; and
15 the metrics calculator may be further configured to calculate
a third delay parameter based upon time elapsed between detection of
the second request message and the second response message.
[0022] The network monitoring device may further comprise:
20 a metrics output connected to the metrics calculator and
25
30
configured to output the estimated time elapsed between the user's first
selection on the web browser in the user device under control of the user
to the first bit received by the user device from the corresponding web
server.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Embodiments of the invention will now be described by way
of example only with reference to the accompanying drawings, in which:
Figure 1 illustrates architecture of an exemplary data
network 10 according to an embodiment of the present invention;
Figure 2 illustrates architecture of an exemplary
communication network 20 according to an embodiment of the present
invention;
10
5 Figure 3 illustrates architecture of an exemplary
communication network 30 according to an embodiment of the present
invention;
Figure 4 shows major processing elements in a probe 100
according to an embodiment of the present invention;
10 Figure 5 is a schematic diagram of physical components of
15
the monitoring probe 100;
Figure 6 is a schematic diagram of the functional
components of the network monitoring device 100 for estimating userperceived
delay for one of CPEs 103 in the data network 1 0;
Figure 7 is a schematic diagram of the functional
components of the monitoring probe 100 for estimating user-perceived
delay for one of CPEs 103 in the data network 20;
Figure 8 is a schematic diagram of the functional
components of the monitoring probe 100 for estimating user-perceived
20 delay for one of CPEs 103 in the data network 30;
Figure 9 is a simplified diagram illustrating message
sequence flow according to an embodiment of the invention; and
Figure 10 is a flowchart illustrating a method for estimating
time elapsed between a user's first selection in a web browser of a user
25 device under control of the user to a first bit received by the user device
from a corresponding web server according to an embodiment of the
invention.
30
DETAILED DESCRIPTIONS OF EXEMPLARY EMBODIMENTS
[0024] In the following description, numerous specific details are set
forth in order to provide a thorough understanding of various illustrative
embodiments of the invention. However, it will be understood by those
skilled in the art that embodiments of the invention may be practiced
35 without some or all of these specific details. In other instances, well
11
5 known process operations have not been described in detail so as to not
unnecessarily obscure pertinent aspects of embodiments being
described. In the drawings, like reference numerals refer to same or
similar functionalities or features throughout the several views.
10 [0025] In order to address the problems or challenges faced by
wireless communication network or data network operator in term of
determining subscriber perspective or user-perspective throughput, the
present disclosure provides a network monitoring device and related
methods/approaches to estimate user-perceived delay in the wireless
15 communication network or the data network by estimating time elapsed
between a user's first selection on an item or hyperlink on a web browser
in a user device under control of the user and a first bit received by the
user device from a corresponding web server.
20 [0026] Figure 1 illustrates architecture of an exemplary data
network 10 according to an embodiment of the present invention.
Referring to Figure 1, a network monitoring device 100 (or a Multiprotocol
probe, hereafter referred to as probe 1 00) connects to a link
between a gateway 101 and an internal router 102. The Internal router
25 102 is further connected to a plurality of customer premise equipments
(CPEs) 103 in the data network 10. For simplicity, only the CPEs 103 are
shown in Figure 1, however there may be multiple computing devices
connected to the data network 10 through corresponding CPEs 103.
Each CPE 103 is assigned at least one IP address. Some or all of the
30 CPEs 103 may be computing devices in which there is disposed a web
browser 104. For small business or a home business, a single IP
address, whether static or dynamic, may be assigned to each CPE 103.
For a large business, each CPE 103 may further connect to a cloud
containing a plurality of servers, so each CPE 103 may be assigned a
35 range of IP addresses, which may be referred to as "aggregated IP
12
5 addresses". In the present disclosure, the CPE 103 represents a
subscriber in the network 10. For simplicity, only one server 170 is shown
in Figure 1, and the server 170 may be a part of the network 10 or
disposed in Internet which is external to the network 10.
10 [0027] The probe 100 transparently receives packets from a
plurality of traffic flows directly associated with each CPE 103. It is noted
that the probe 100 merely passively extracts copies of packets from the
traffic flows in the data network 10, transparently processes the received
packets and does not affect transmission of the packets in the data
15 network 10. The probe 100 is further configured to generate statistical
reports based on the received packets and send the generated reports to
a customer experience management (CEM) system 150 external to the
probe 100. In other embodiments, the CEM 150 can be replaced by other
data analysis processing devices.
20
[0028] The invention may be applied to any data network using
different communication protocol standards, e.g. Long Term Evolution
(L TE) network, 3G network as defined in Third Generation Partnership
Project (3GPP) Technical Specifications. In different data networks, the
25 probe 100 may be deployed to sniff packets from a high speed link over
different interfaces. For example, in the 3G network, the Probe 100 may
be deployed to sniff packets from a high speed link over Gn interface as
shown in Figure 2. In another example, in the L TE network as shown in
Figure 3, the probe 100 may sniff traffic flows from L TE interfaces, for
30 instance, LTE S1-U, S4, S11 and S12 interfaces over high speed links.
[0029] Figure 2 illustrates architecture of an exemplary
communication network 20 according to an embodiment of the present
invention. Referring to Figure 2, in a 3G network, the probe 100 may
35 connect to a link between Serving GPRS Support Node (SGSN) 220 and
13
5 Gateway GPRS Support Node (GGSN) 230 to extract traffic flows. The
traffic flows originate from, or transmit to, a user equipment (UE) 202
which is connected with the SGSN 220 via a radio network controller
(RNC) 203 and a base station 201. The UE202 is connected to the base
station 201 through an air interface Uu. The UE 202 receives packets
10 from, and transmits packets to, the Internet via the GGSN 230. There is
also a web browser 204 disposed in the UE 202. As shown in Figure 2,
the probe 100 may extract directional traffic flows from the Control-plane
(C-Piane) and the User-Plane (U-Piane) via the Gn interface in the
communication network 20, and then generate statistical reports based
15 on packets received from the directional traffic flows and send the
generated reports to a CEM system 150 external to the probe 100. In the
present disclosure, the UE 202 or the user device represents a
subscriber in the network 20. For simplicity, only one server 270 is
shown in Figure 2, and the server 270 may be part of the network 20 or
20 disposed in Internet which is external to the network 20.
[0030] Figure 3 illustrates architecture of an exemplary
communication network 30 according to an embodiment of the present
invention. Referring to Figure 3, the probe 100 is configured to extract
25 traffic flows from both the U-Piane and the C-Piane. The U-Piane traffic
flows basically relate to Internet Protocol (IP) data packets transported
between a UE 322 through the evolved NodeB (eNB) 321 and any
servers in Cloud/Internet. Usually, the IP packets travel through high
speed links between mobile devices/UEs and Cloud/Internet via Serving
30 Gateway (S-GW)/ Service General Packet Radio Service Support Node
(SGSN) 320. The C-Piane traffic flows are related to control information,
such as those transported between eNB 321 and Mobility Management
Entity (MME) 314 for customers. There is also a web browser 304
disposed in the UE 322. As shown in Figure 3, the probe 100 may
35 connect to a S1-U interface between eNB 321 and S-GW/SGSN 320 to
14
5 extract directional traffic flows from the U-P lane, and connect to a S 1-
MME between eNB 321 and MME 314 to extract directional traffic flows
from the C-Piane. In some embodiments, the probe 100 is connected to
extract traffic flows from C-Piane via other C-Piane interface, such as
S6a interface between Home Subscriber Server (HSS) 311 and the MME
10 314. For simplicity, only one server 370 is shown in Figure 3, and the
server 370 may be part of the network 30, or disposed in Internet which
is external to the network 30.
[0031] Prior to describing the operation of probe 100, the basic unit
15 of statistical data collection, i.e. the traffic flow in the probe 100, is
explained. In the present disclosure, three types of traffic flows are
described when describing operations of probe 100. The concept of
traffic flows is important to understand the U-Piane processing. Firstly, a
directional Traffic Flow in Transmission Control Protocol/Internet Protocol
20 (TCP/IP) networks is defined as: "a flow is a series of packets that share
the same source and destination IP addresses, source and destination
ports, and IP protocol. This is also called a five-tuple IP flow'. The fivetuple
may include: a source IP address; a source port number; a
destination IP address; a destination port number; and an IP protocol.
25
[0032] Both source and destination addresses must be of the same
type, i.e. 1Pv4 or 1Pv6 and the flow is directional. If the source and
destination are swapped, it becomes a different flow. The IP protocol
member specifies the Layer 4 protocol, e.g. TCP, UDP. In the present
30 disclosure, the flow is also called a directional traffic flow.
[0033] In 3G/L TE networks, on U-P lane, the directional traffic flow
may be characterised by five-tuple and Tunnel End Identifier (TEID} due
to IP encapsulation used in tunnelling of directional traffic flows.·
15
5 Directional traffic flows transmitted in different directions are assigned
different TElOs. In 3G/L TE networks, the TEID is 32 bits long.
[0034] In order to reliably detect application layer protocols, the
probe 100 may use a deep packet inspection (DPI) engine to analyse
10 traffic flows in both directions together. That is, the probe 100 analyses
bi-directional traffic flows. In the present disclosure, analysis of traffic
flows together in both directions is referred to as a "bi-directional traffic
flow". A bi-directional traffic flow groups the two directional traffic flows
corresponding to opposite directions together. That is to say, the source
15 of one directional traffic flow corresponds to the destination of the other
directional traffic flow in the opposite direction. The bi-directional traffic
flow is specified by a five-tuple similar to the directional traffic flow, which
may include: a lower IP address; a lower port number; an upper IP
address; an upper port number; and a Layer 4 protocol.
20
[0035] In a bi-directional traffic flow, instead of a source and a
destination address, the five-tuple includes a lower and an upper
address. "Lower" refers to a numerically smaller value and upper refers
to a numerically greater value. Lower ·port number refers to the port
25 associated with the lower IP address and not the numerically lower port
number.
[0036] Thus, suppose the source address is 192.168.1.17 port 2192
and the destination is 11.20.5.34 port 80, the lower IP address and port
30 are 11.20.5.34 port 80 and the upper IP address and port are
192.168.1.17 port 2192. If the source is 11.20.5.34 port 80 and the
destination is 192.168.1.17 port 2192 then the lower IP and port are still
11.20.5.34 port 80 and the upper IP address and port are still
192.168.1.17 port 2192. The five-tuple is the same regardless of the
35 source and destination. Thus the direction of data transfer cannot be
16
5 identified from the bi-directional traffic flow five-tuple. The meaning of the
Layer 4 protocol field is the same as that of the IP protocol in the
directional traffic flow five-tuple.
[0037] · The real IP traffic traversing in the communication network
10 and data network is related to application traffic flow(s) of end
users/subscribers. The application traffic flow is a concept used in the
statistical reports generated by the probe 100 and sent to, for example,
the CEM 150 or an external data analysis processing device for further
processing and analysis. An application traffic flow is specified by a
15 three-tuple, which may include: an internal IP address; an external IP
address; and an application 10 (Identifier). The internal I P address is the
IP address of the UE or the mobile phone and is internal to the operator's
network. The external address is external to the operator's network, most
likely in the Internet. The application 10 corresponds to the Layer 7 or
20 application layer protocol, e.g. HTTP, IMAP, and so forth. This threetuple
is bi-directional similar to the five-tuple of a bi-directional flow. It is
also similar in that the application 10 generally identifies the destination
port and the IP protocol, except when a server is using an
unconventional port number for that application/protocol. Essentially, an
25 application traffic flow is the aggregation of possibly multiple bidirectional
traffic flows. For example, suppose a UE is connected to a
website and has multiple pages open, there will be multiple bi-directional
flows each with a different source port in the HTTP between that UE and
the web server. In the present disclosure, an application traffic flow may
30 refer to traffic flows from one UE with the same application protocol, or all
traffic flows to a specific destination/application server belonging to a
particular application protocol.
[0038] In order to calculate statistical data of an active traffic flow(s)
35 such as throughput of a particular subscriber on U-P lane, the probe 100
17
5 receives IP packets from directional traffic flows on both C-Piane and UPiane,
generates statistical data for bi-directional traffic flows and then
uses the generated statistical data and other related identification
information extracted from the bi-directional traffic flows to calculate the
statistical data of a particular application traffic flow/particular directional
10 traffic flow on U-Piane. The probe 100 may further use the identifier
information obtained from C-Piane such as Fully Qualified Tunnel End
Identifier (FTEID), International Mobile Subscriber Identity (IMSI) or
Globally Unique Temporary ID (GUTI) to correlate statistical data of a
particular application traffic flow/particular directional traffic flow with a
15 subscriber in the data network. After the probe 100 calculates the
statistical data of traffic flows corresponding to a large number of
customers/subscribers, the calculated statistical data are output or
transferred from the probe 100 to the CEM 150 as shown in Figures 1-4.
20 [0039] Figure 4 shows major processing elements in a probe 100
according to an embodiment of the present invention. The process of
statistical calculation in the probe 100 may be explained with reference to
Figure 4. As shown in Figure 4, the probe 100 may include a link
processor (LP) 20 connected to a correlation processor (CP) 30. In
25 another embodiment, the probe 100 may include more than one LP 20
connected to the CP 30. When a plurality of LPs 20 are used to process
incoming traffic flows, the LPs work in parallel to extract directional traffic
flows, and apply detection on Internet Protocol (IP) packets on each
directional traffic flow in order to extract information from the IP packets.
30
[0040] In order to calculate statistical data of all directional traffic
flows or application traffic flows from one UE belonging to a particular
application protocol, e.g. HTTP, FTP etc, the probe 100 may use the DPI
engine operating in the LP 20 to obtain application layer protocol of the
35 received packets in bi-directional traffic flows. The application layer
18
5 protocol has unique Application ID in the three-tuple definition of the
application traffic flow.
[0041] Before each request-response message/packet for any
application traffic flow occurs on U-Piane, there may be at least one or
10 some control signalling or control messages transferred on C-Piane, and
the LP 20 of the Probe 100 may extract customer/subscriber information
thereon, such as FTEID, IMSI, GUTI, eNB-UE-S1APID, MME-UES1APID
and so forth. Thus, the CP 30 receiving output from LPs 20 will
further correlate the application traffic flows with the customer/subscriber
15 information in the control signalling or control messages. Subsequently,
the CP generates a traffic flow statistical data report regarding individual
customer(s)/subscriber(s) and transmits the report to the CEM 150 or an
external data processing analysis device.
20 [0042] According to an embodiment of the invention, each LP 20 in
the probe 100 reports statistical data of a bi-directional traffic flow in a
preconfigured data structure to the CP 30. Each data structure is a
nested structure and may include at least the following pre-configured
information: an upper IP address; a lower IP address; an upper port
25 number; a lower port number; an Application ID; a downlink statistical
data structure; and an uplink statistical data structure.
[0043] The downlink statistical data structure for one bi-directional
traffic flow includes at least the following information: "Number of bytes"
30 received from the downlink traffic flow; "Number of packets" received
from the downlink traffic flow; "Active Second Vector" for current report
period, which is configured to record the active seconds of downlink
traffic flow within the current reporting period; "Period Octet Vector" for
current report period, which is configured to accumulate and store
35 statistical data of the downlink traffic flow within the current reporting
19
J ,
5 period, e.g. the number of bytes and the number of packets transferred in
the downlink traffic flow; FTEID of the directional traffic flow. In 3G/L TE
networks, FTEID includes TEID and Layer 3 IP address of GTP packets.
This Layer 3 IP address is only for routing encapsulated IP packets
inside the L TE network.
10
[0044] The uplink statistical data structure for the same bidirectional
traffic flow includes at least the following information: "Number
of bytes" received from the uplink traffic flow; "Number of packets"
received from the uplink traffic flow; "Active Second Vector" for current
15 report period, which is configured to record the active seconds of uplink
traffic flow within the current reporting period; "Period Octet Vector" for
current report period, which is configured to accumulate and store
statistical data of the uplink traffic flow within the current reporting period,
e.g. the number of bytes and the number of packets transferred in the
20 uplink traffic flow; FTEID of the directional traffic flow.
[0045] Figure 5 is a schematic diagram of the physical components
of the probe 100. The probe 100 includes a processor unit 131, a
storage unit 132, an output network interface 133, and one or more input
25 network interfaces 134a ... 134n. It is envisaged that the probe 100 will
typically include more than one input network interface 134.
However,those skilled in the art will appreciate that the probe 100 may
include only one input network interface 134. For example, in one
embodiment where the monitoring probe 100 is configured to only
30 monitor for the control plane messages transmitted from the eNB 321 to
the MME 314 on the S1-MME interface, the probe 100 may have only
one input network interface 134.
[0046] Each of the input network interfaces 134a ... 134n is
35 connected to a respective one of the eNB 321, MME 314, HSS 311 and
20
5 S-GW 320 on a high-speed link. The processor unit 131 is configured to
implement (or execute) a number of software modules based on program
code and/or data stored in the storage unit 132. The storage unit 132
stores program code for implementing software modules for identifying a
user plane identifier of the UE 202/UE 322 and also correlate the control
10 plane identifier and the user plane identifier of the UE 202/UE 322.
[0047] Figure 6 is a schematic diagram of the functional
components of the monitoring probe 100 for estimating user-perceived
delay for a CPE 103 in the data network 10. In this embodiment, the
15 functional components are software modules implemented by the
processor unit 131 of the probe 100. However, persons skilled in the art
will appreciate that one or more of the functional components could
alternatively be implemented in some other way, for example, by one or
more dedicated circuits.
20
[0048] One of the software modules implemented by the processor
unit 131 is a datagram monitor 313. The datagram monitor 313 is
adapted to monitor one or more of the network devices of the data
network 10 for receipt of at least control plane messages and/or user
25 plane data packets. For example, the datagram monitor 313 may be part
of the LP 20. Each of the control plane messages/user plane data
packets comprises at least one control plane identifier. At least one of the
control plane messages/user plane data packets comprises at least one
user device identifier, and at least another one of the control plane
30 messages comprises at least one user plane identifier. For example, the
datagram monitor 313 may be configured to detect the type of messages
received from the network 10.
[0049] Referring to Figure 6, the processor unit 131 is electrically
35 connected to at least one Input Network Interface 134a, 134b. In some
21
5 embodiments, the processor unit 131 is electrically connected to Input
Network Interfaces 134a-134b. Also, the processor unit 131 is connected
to the storage unit 132 and the output network interface 133. The
datagram monitor 313 monitors a gateway 101 and a router 102 for
receipt of control plane messages or user plane data packets. Other
10 software modules implemented by the processor unit 131 are a metrics
calculator 318 and a metrics output 319. The metrics calculator 318
analyses the IP packets received on traffic flows corresponding to each
subscriber in the data network 10, calculates throughput of each
subscriber over preconfigured monitoring period, and then outputs the
15 calculated throughput of each subscriber through the metrics output 319
(via the output network interface 133) to the GEM 150 or another data
analysis processing device. For example, the metrics calculator 318 and
the metrics output 319 may be a part of the LP 30. In another example,
the metrics calculator 318 may be configured to calculate time elapsed
20 between a first message and a second message subsequent to the first
message received by the datagram monitor 313.
[0050] Figure 7 is a schematic diagram of the functional
components of the probe 100 for estimating user-perceived delay for a
25 user device in the communication network 20. In this embodiment, the
functional components are software modules implemented by the
processor unit 131 of the probe 100. However, those skilled in the art
will appreciate that one or more of the functional components could
alternatively be implemented in some other way, for example, by one or
30 more dedicated electronic circuits.
[0051] The datagram monitor 313 is adapted to monitor one or
more of the network devices of the communication network 20 for receipt
of at least control plane messages and/or user plane data packet. Each
35 of the control plane messages/user plane data packets comprises at
22
5 least one control plane identifier. At least one of the control plane
messages/user plane data packets comprises at least one user device
identifier, and at least another one of the control plane messages
comprises at least one user plane identifier. For example, the datagram
monitor 313 may be a part of the LP 20. For example, the datagram
10 monitor 313 may be configured to detect the type of messages received
from the network 20.
[0052] Referring to Figure 7, the processor unit 131 is electrically
connected to at least one Input Network Interfaces 134a, 134b. In some
15 embodiments, the processor unit 131 is electrically connected to Input
Network Interfaces 134a-134b. Also, the processor unit 131 is connected
to the storage unit 132 and the output network interface 133. The
datagram monitor 313 monitors the GGSN 201 and the SGSN 202 for
receipt of control plane messages or user plane data packets. The
20 metrics calculator 318 analyses the IP packets received on traffic flows
corresponding to each subscriber in the communication network 20,
calculates throughput of each subscriber over a preconfigured monitoring
period, and then outputs the calculated throughput of each subscriber
through metrics output 319 (via the output network interface 133) to the
25 CEM 150 or another data analysis processing device. For example, the
metrics calculator 318 and the metrics output 319 may be a part of the
LP 30. In another example, the metrics calculator 318 may be configured
to calculate time elapsed between a first message and a second
message subsequent to the first message received by the datagram
30 monitor 313.
[0053] Figure 8 is a schematic diagram of the functional
components of the probe 100 for estimating user-perceived delay for a
user device in the communication network 30. In this embodiment, the
35 functional components are software modules implemented by the
23
5 processor unit 131 of the probe 100. However, those skilled in the art will
appreciate that one or more of the functional components could
alternatively be implemented in some other way, for example, by one or
more dedicated circuits.
10 [0054] The datagram monitor 313 is adapted to monitor one or
more of the network devices of the communication network 30 for receipt
of at least control plane messages and/or user plane data packets. Each
of the control plane messages/user plane data packets comprises at
least one control plane identifier. At least one of the control plane
15 messages/user plane data packets comprises at least one user device
identifier, and at least another one of the control plane messages
comprises at least one user plane identifier. For example, the datagram
monitor 313 may be part of the LP 20. For example, the datagram
monitor 313 may be configured to detect the type of messages received
20 from the network 30.
[0055] Referring to Figure 8, the processor unit 131 is electrically
connected to at least Input Network Interfaces 134a, 134b, 134c, 134d in
order to monitor control plane messages or user plane data packets
25 coming from the S-GW 320, the eNB 321 and MME 314 via the Input
Network Interfaces 134a, 134b, 134c, 134d respectively. In some
embodiments, the processor unit 131 is connected to Input Network
Interfaces 134a-134b for monitoring user plane data packets coming
from the S-GW 320 and the eNB 321. Also, the processor unit 131 is
30 connected to the storage unit 132 and the output network interface 133.
The datagram monitor 313 monitors the eNB 321 and the MME 314 for
receipt of control plane messages or user plane data packets. The
metrics calculator 318 analyses the IP packets received on traffic flows
corresponding to each subscriber in the communication network 30,
35 calculates throughput of each subscriber over preconfigured monitoring
24
5 period, and then outputs the calculated throughput of each subscriber
through metrics output 319 (via the output network interface 133) to the
GEM 150 or another data analysis processing device. For example, the
metrics calculator 318 and the metrics output 319 may be a part of the
LP 30. For another example, the metrics calculator 318 may be
10 configured to calculate time elapsed between a first message and a
second message subsequent to the first message received by the
datagram monitor 313.
[0056] The probe 100 shown in Figures 1 to 8 is proposed to
15 estimate time elapsed from an end user's first selection command in a
web browser of the user device under control of the end user to a first bit
or a first byte received from a corresponding web server, e.g, the servers
170, 270, 370. For example, the probe 100 can be deployed in a wireless
communication network or a data network for sniffing user plane data
20 packets or control plane messages or signaling. For example, Figure 3
illustrates the probe 100 deployed in a L TE network where control plane
messages may be extracted over S1-MME, S11, S6a interface; the user
plane data packets may be extracted over S1-U interface between the
eNB 321 and the S-GW 320. Therefore, the user data transmissions in
25 uplink and downlink can be easily detected for UEs connected to the
eNB 321.
[0057] In another example, the probe 100 can be deployed in a 3G
network, e.g., the network 20, to sniff user data packets over Gn
30· interface and sniff packet for application flow corresponding to any UE in
the operator network. However, as can be seen in Figure 9 below, for an
application flow of a UE, Internet delay or Radio Delay, the Application
Response Time should be accurately measured.
25
5 [0058] Figure 9 is a simplified diagram illustrating message
sequence flow according to an embodiment of the invention. Figure 9
illustrates message transmissions P1, P2, P5, P6 originating from a UE
(or a CPE) monitored by probe 100 to a corresponding server 170, 270,
370, or message transmissions P3, P4, P7, P8 originating from the
10 corresponding server 170, 270, 370 to the UE (or the CPE). The userperceived
delay, which is defined as time elapsed from a first selection of
a webpage object by the end user on the UE (or the CPE) to the first bit
or first byte received by the UE (or the CPE), is illustrated by time 05.
15 [0059] Currently, probe 100 can directly measure time durations 01,
02 and 03, but cannot directly measure the time taken for the message
transmission path along P1 and P8. By close monitoring of messages
transmitted from, and received by, the UE (or the CPE), and also by
close monitoring of messages responded to by the corresponding server
20 in Internet, it is observed that when an end user requests to download a
web page after the universal resource locator (URL) is input or simply by
clicking a hyperlink in another web page, the first message transmitted
from the smartphone or the smart device is a synchronization packet
(SYN). The first packet sent across a TCP connection is known as a SYN
25 packet. For example, when the end user enters
"http://www.cellossoftware.com" on the web browser, the first IP packet
transmitted from the user device could be a SYN packet to the HTTP port
on a web server responsible for the URL of "www.cellossoftware.com". In
this case, the browser on the user device attempts to notify the
30 corresponding web server that the user device wants to connect with the
web server.
[0060] The transmission from the user device (e.g, smartphone or
computing device) to a corresponding server in Internet is depicted by
35 transmissions P1 and P2 in Figure 9. When probe 100 is deployed in a
26
5 wireless communication network, it may be connected to a user interface
such as S1-U interface connected to S-GW 320, and then the S-GW 320
further connects to the Internet. Probe 100 can record the time T1
(according to timestamp assigned by network interface card or the input
network interface 134) when the SYN packet is detected.
10
[0061] In response to the SYN packet received from the user
device, the corresponding server in Internet may transmit a SYN ACK
packet to the user device. The transmission of the SYN ACK packet is
depicted by transmissions P3 and P4 in Figure 9. Probe 100 may record
15 time T2 (according to timestamp assigned by network interface card or
the input network interface 134) when the SYN ACK packet from the
corresponding server is detected.
[0062] In the present context, the time difference between the T1
20 and T2 is .Internet Delay, and the Internet Delay is depicted by D1 in
Figure 9. Alternatively, D1 may be interpreted as the time elapsed
between detections of a synchronization message and a corresponding
synchronization acknowledgement message at probe 100.
25 [0063] In response to the SYN ACK packet received from the
corresponding server, the user device consecutively transmits SYN ACK
ACK packet (whose transmission depicted as a transmission P5 in
Figure 9) and then a GET request packet containing a request message
(depicted as a transmission P6 in Figure 9). Probe 100 can record time
30 T3 (according to timestamp assigned by network interface card or the
input network interface 134) when the SYN ACK ACK packet and the
GET request packet is detected. The above-mentioned SYN message,
SYN ACK message, SYN ACK ACK messages correspond to TCP layer
(transport layer) messages.
35
27
5 [0064] The time difference between T2 and T3 may be called a
Radio Delay if probe 100 is deployed in a wireless communication
network. The Radio Delay is a wireless network delay between a
gateway of the wireless network and the user device. The Radio Delay is
depicted by D2 in Figure 9. Alternatively, D2 may be interpreted as the
10 time elapsed between detections of the synchronization
acknowledgement message and a GET request message (carried by
GET request packet) at the probe 100.
[0065] In response to the SYN ACK ACK packet and GET request
15 packet received from the user device, the corresponding server
processes the request message and provides a segment1 (the first
segment) of the requested web content in a GET response packet
(containing a GET response message carrying the segment 1) to the
user device. The transmissions of the GET response packet (containing
20 the response message carrying the segment 1) are depicted by
transmissions P7 and P8. Probe 100 can record time T4 (according to
timestamp assigned by network interface card or the input network
interface 134) when the GET response packet corresponding to the user
device is detected. The above-mentioned GET request message and
25 GET response message are corresponding to HTIP layer (application
layer) messages.
[0066] The time difference between the T3 and T4 may be referred
to as Application Response Time .. The Application Response Time is
30 Internet Delay plus Server processing time (depicted by D4) of the
corresponding server, and the Application Response Time is depicted by
D3 in Figure 9. Alternatively, D3 may be interpreted as the time elapsed
between detections of the GET request message and a GET request
message (containing GET response ;:;egment 1) by probe 100.
35
28
5 [0067] However, probe 100 cannot directly measure the time taken
for the transmissions P1 and PS. By close monitoring of the packet
traversing in the wireless communication network it is observed that time
taken from the gateway of the network to the user device over the
transmission P4 is similar to time taken from the gateway of the network
10 to the user device over the transmission PS. Also, the time (depicted by a
single trip radio delay, SRD in Figure 9) taken for the SYN ACK ACK
message or the GET request message from the user device to arrive at
the gateway of the network is similar to the time taken for SYN message
transmitted from the user device to the 8-GW over transmission P1.
15
[0068] Since the radio delay, 02, can represent the time taken for
transmissions SRD and P4, it is proposed to estimate the time "from first
click to first bit received" as 01+02*2+03. That is, 05, as time elapsed
between the user's first selection on the web browser in the user device
20 under control of the user to the first bit received by the user device from
the corresponding web server, may be estimated according to an
equation {1) below:
25
D5=D1+D2x2+D3 ... Equation (1),
[0069] wherein, the first delay parameter 01 is time elapsed
between detections of the first request message and the first response
message; the second delay parameter 02 is time elapsed between
detections of the first response message and the second request
30 message; the third delay parameter 03 is time elapsed between
detections of the second request message and the second request
message.
[0070] In equation (1), 01 may be called the Internet Delay; 02 may
35 be called the radio delay; 03 may be called the Application response
29
5 delay; and 05 is the total amount of time from a first click (a first selection
command on web browser of the user device) by the end user to a first
bit downloaded/received by the user device (from the corresponding
server).
10 [0071] According to measurements in live wireless communication
networks the proposed method can accurately estimate time "from first
click to first bit received", based on what the probe can directly measure.
The proposed method can efficiently provide the estimated delay from
first click to first bit received.
15
[0072] Figure 10 is flowchart illustrating a method for estimating
time elapsed between a user's first selection on a web browser in a user
device under control of the user to a first bit received by the user device
from a corresponding web server. Referring to Figures 6 to Figure 10, the
20 method of for estimating a user-perceived network may include the
following steps A-1 to A-4, and can be applied to any of communication
networks 10, 20 or 30.
[0073] At step A-1, the metrics calculator 318 of probe 100 is
25 configured to calculate a first delay parameter (i.e., the first delay
parameter 01) based upon time elapsed between detections of a first
request message (e.g., the SYN packet transmitted from the user
device/CPE to the corresponding server) and a first response message
(e.g., the SYN ACK packet transmitted from the corresponding server to
30 the user device/CPE). The first request message corresponds to the
user's first selection on the web browser, and the first response message
is an acknowledgement message transmitted by the corresponding web
server in response to the first request message received by the
corresponding web server.
35
30
5 [0074] At step A-1, datagram monitor 313 of probe 100 first
monitors one network equipment (e.g, a router 102, a SGSN 220 or an
eNB 321) in a network 10, 20 or 30 for receipt of the first request
message corresponding to the user's first selection on the web browser.
Then, at the same step A-1, probe 100 continues to monitor the other
10 netWork equipment (e.g., a gateway 101, a GGSN 230, a S-GW 320) in
the network 10, 20 or 30 or in the wireless communication network for
receipt of the first response message, where the first response message
is an acknowledgement message transmitted by the corresponding web
server in response to receipt of the first request message. Subsequently,
15 metrics calculator 318 of probe 100 receives the time instants of
detecting the first request message and the first response message from
datagram monitor 313, and is configured to calculate the first delay
parameter 01 based upon time elapsed between detections of the first
request message and the first response message.
20
[0075] The first request message corresponds to a transport control
protocol (TCP) synchronization packet. The first response message is an
acknowledgement message at TCP layer transmitted by the
corresponding web server in response to the first request message
25 received by the corresponding web server. Additionally, datagram
monitor 313 of probe 100 obtains time instants of messages assigned by
the input network interface 134a and/or 134b which are implemented as
network interface cards.
30 [0076] At step A-2, metrics calculator 318 is configured to calculate
a second delay parameter (i.e., the second delay parameter 02) based
upon time elapsed between detections of the first response message and
a second request message (e.g., a GET Request message), where the
second request message is transmitted by the user device in response to
35 the first response message received by the user device.
31
5
[0077] At step A-2, datagram monitor 313 firstly monitors the
network equipment (e.g., the router 102, the SGSN 220 or the eNB 321)
in the network 10, 20 or 30 for receipt of the second request message.
Then, at the same step A-2, metrics calculator 318 is configured to
10 receive the time instants of detecting the first response message and the
second request message from datagram monitor 313, and configured to
calculate the second delay parameter 02 based upon time elapsed
between detections of the first response message and the second
request message. Additionally, the second request message is a
15 Hypertext Transfer Protocol (HTTP) GET Request message.
[0078] At step A-3, metrics calculator 318 is configured to calculate
a third delay parameter (i.e., the third delay parameter 03) based upon
time elapsed between detections of the second request message and a
20 second response message (e.g., GET Response message) which is
transmitted by the corresponding web server in response to the second
request message received by the corresponding web server. The second
response message is a Hypertext Transfer Protocol (HTTP) GET
Response message, and the second response message carries the first
25 bit which is received by the user device.
[0079] At step A-3, datagram monitor 313 firstly monitors the other
network equipment (e.g., a gateway 101, a GGSN 230, a S-GW 320) in
the network 10, 20 or 30 for receipt of the second response message.
30 Then, at the same step A-3, metrics calculator 318 is configured to
receive the time instants of detecting the second response message and
the second request message from datagram monitor 313, and configured
to calculate a third delay parameter based upon time elapsed between
detections of the second request message and the second response
35 message.
32
5
[0080] At step A-4, metrics calculator 318 is further configured to
estimate the time elapsed between the user's first selection on the web
browser in the user device under control of the user to the first bit
received by the user device from a corresponding web server according
10 to the first delay parameter 01, the second delay parameter 02 and the
third delay parameter 03. In particular, metrics calculator 318 estimates
the time elapsed between the user's first selection on the web browser in
the user device under control of the user to the first bit received by the
user device from a corresponding web server by adding the first delay
15 parameter 01, twice the second delay parameter 02 and the third delay
parameter 03. That is, metrics calculator 318 estimates the userperceived
delay 05 according to equation (1).
[0081] At step A-4, metrics output 319 of probe 100 is configured to
20 output an external processing device the estimated time elapsed
between the user's first selection on the web browser in the user device
under control of the user to the first bit received by the user device from
the corresponding web server. The external processing device can be a
CEM 150 or a customer data analysis device (not shown).
25
[0082] The preceding exemplary embodiments of the present
invention may be implemented in software/instruction codes/application
logic/instruction seUcomputer program codes (executed by one or more
processors), may be fully implemented in hardware, or implemented in a
30 combination of software and hardware. For instance, the software (e.g.,
application logic, an instruction set) is maintained on any one of various
conventional computer-readable media. In the present disclosure, a
"computer-readable medium" may be any storage media or means that
can carry, store, communicate, propagate or transport the instructions for
35 use by or in connection with an instruction execution system, apparatus,
33
5 or device, such as a network monitoring device shown in Figures 5 to 8.
A computer-readable medium may include a computer-readable storage
medium (e.g., a physical device) that may be any media or means that
can carry or store the instructions for use by or in connection with a
system, apparatus, or device, such as a computer or a communication
10 device. For instance, the storage unit 132 may include the computerreadable
medium which may include computer program code, when
executed by the processor unit 131, may cause the network monitoring
device and related methods/approaches to estimate user-perceived
delay in the communication network or the data network by performing
15 procedures/steps illustrated in Figures 10.
[0083] Further aspects of the network monitoring probe 100 will be
apparent from the above description of the network monitoring probe
100. Persons skilled in the art will also appreciate that any of the
20 methods described above could be embodied in program code. The
program code could be supplied in a number of ways, for example on a
tangible computer readable medium, such as a disc or a memory or as a
data signal.
25 [0084] It is to be understood that, if any prior art is referred to
herein, such reference does not constitute an admission that the prior art
forms a part of the common general knowledge in the art in any country.
[0085] In the claims which follow and in the preceding description of
30 the invention, except where the context requires otherwise due to
express language or necessary implication, the word "comprise" or
variations such as "comprises" or "comprising" is used in an inclusive
sense, that is to specify the presence of the stated features but not to
preclude the presence or addition of further features in various
embodiments of the invention.

We claim:
1. A method for estimating time elapsed between a user's first
selection on a web browser of a user device under control of the user to
a first bit received by the user device from a corresponding web server
comprising:
10 calculating, by a network monitoring device, a first delay parameter
based upon time elapsed between detection of a first request message
and a first response message, wherein the first request message
corresponds to the user's first selection on the web browser and the first
response message is transmitted by the corresponding web server in
15 response to the first request message received by the corresponding
web server;
calculating, by the network monitoring device, a second delay
parameter based upon time elapsed between detection of the first
response message and a second request message, wherein the second
20 request message is transmitted by the user device in response to the first
response message received by the user device;
calculating, by the network monitoring device, a third delay
parameter based upon time elapsed between detection of the second
request message and a second response message which is transmitted
25 by the corresponding web server in response to the second request
message received by the corresponding web server; and
estimating the time elapsed between the user's first selection on the
web browser in the user device under control of the user to the first bit
received by the user device from the corresponding web server in
30 accordance with the first delay parameter, the second delay parameter
and the third delay parameter.
2. The method of claim 1, wherein the step of estimating the time
elapsed between the user's first selection on the web browser in the user
35
5 device under control of the user to the first bit received by the user
device from a corresponding web server comprises:
estimating the time elapsed between the user's first selection on the
web browser in the user device under control of the user to the first bit
received by the user device from a corresponding web server by adding
10 the first delay parameter, twice the second delay parameter and the third
delay parameter.
3. The method of claim 2, wherein the step of calculating the first
delay parameter comprises:
15 monitoring, by the network monitoring device, one network
equipment in a network for receipt of the first request message
corresponding to the user's first selection on the web browser;
monitoring, by the network monitoring device, another network
equipment in the network for receipt of the first response message,
20 wherein the first response message is an acknowledgement message
transmitted by the corresponding web server in response to receipt of the
first request message;
calculating, by the network monitoring device, the first delay
parameter based upon time elapsed between detection of the first
25 request message and the first response message.
4. The method of claim 3, wherein the step of calculating the second
delay parameter comprises:
monitoring, by the network monitoring device, the network
30 equipment in the network for receipt of the second request message;
calculating, by the network monitoring device, the second delay
parameter based upon time elapsed between detection of the first
response message and the second request message.
36
5 5. The method of claim 4, wherein the step of calculating the third
delay parameter comprises:
monitoring, by the network monitoring device, the another network
equipment in the network for receipt of the second response message;
calculating, by the network monitoring device, the third delay parameter
10 based upon time elapsed between detection of the second request
message and the second response message.
6. The method of claim 1, wherein the first request message
corresponds to a transport control protocol (TCP) synchronization
15 packet.
7. The method of claim 6, wherein the first response message
corresponds to an acknowledgement message at TCP layer transmitted
by the corresponding web server in response to the first request
20 message received by the corresponding web server.
25
30
8. The method of claim 7, wherein the second request message
corresponds to a Hypertext Transfer Protocol (HTTP) GET Request
message.
9. The method of claim 8, wherein the second response message
corresponds to a Hypertext Transfer Protocol (HTTP) GET Response
message, and wherein the second response message carries the first bit
which is received by the user device.
10. The method of claim 1, further comprising:
outputting, by the network monitoring device, to an external processing
device the estimated time elapsed between the user's first selection on
the web browser in the user device under control of the user to the first
35 bit received by the user device from the corresponding web server
37
5
11. A network monitoring device for estimating time elapsed between a
user's first selection on a web browser in a user device under control of
the user to a first bit received by the user device from a corresponding
web server ( comprising:
10 a datagram monitor configured to monitor at least two network
devices in a network for detecting messages;
a metrics calculator connected to the datagram monitor configured
to:
calculate a first delay parameter based upon time elapsed between
15 detection of a first request message and a first response message,
wherein the first request message corresponds to the user's first
selection on the web browser and the first acknowledgement message is
transmitted by the corresponding web server in response to the first
request message received by the corresponding web server;
20 calculate a second delay parameter based upon time elapsed
between detection of the first response message and a second request
message, wherein the second request message is transmitted by the
user device in response to the first response message received by the
user device;
25 calculate a third delay parameter based upon time elapsed between
detections of the second request message and a second response
message which is transmitted by · the corresponding web server in
response to the second request message received by the corresponding
web server; and
30 estimate the time elapsed between the user's first selection on the
35
web browser in the user device under control of the user to the first bit
received by the user device from the corresponding web server in
accordance with the first delay parameter, the second delay parameter
and the third delay parameter.
38
5 12. The network monitoring device of claim 11, wherein the metrics
calculator is further configured to:
estimate the time elapsed between the user's first selection on the
web browser in the user device under control of the user to the first bit
received by the user device from a corresponding web server by adding
10 the first delay parameter, twice the second delay parameter and the third
delay parameter.
13. The network monitoring device of claim 11, wherein the datagram
monitor is further configured to:
15 monitor one network equipment in a network for receipt of the first
request message corresponding to the user's first selection on the web
browser;
monitor another network equipment in the network for receipt of the
first response message, wherein the first response message is an
20 acknowledgement message transmitted by the corresponding web server
in response to receipt of the request message, and wherein
25
the metrics calculator is further configured to calculate the first
delay parameter based upon time elapsed between detection of the first
request message and the first response message.
14. The network monitoring device of claim 13, wherein the datagram
monitor is further configured to:
monitor the network equipment in the network for receipt of the
second request message; and
30 the metrics calculator is further configured to calculate the second
delay parameter based upon time elapsed between detection of the first
response message and the second request message.
15. The network monitoring device of claim 14, wherein:
35 the datagram monitor is further configured to:
39
5 monitor the other network equipment in the network for receipt of
10
the second response message; and wherein
the metrics calculator is further configured to calculate the third
delay parameter based upon time elapsed between detection of the
second request message and the second response message.
16. The network monitoring device of claim 11, further comprising:
a metrics output connected to the metrics calculator and configured
to output the estimated time elapsed between the user's first selection on
the web browser in the user device under control of the user to the first
15 bit received by the user device from the corresponding web server.
17. A method for estimating time elapsed between a user's first
selection on a web browser in a user device under control of the user to
a first bit received by the user device from a corresponding web server
20 comprising:
monitoring, by a network monitoring device, one network equipment
in a network for receipt of a first request message corresponding to the
user's first selection on the web browser;
monitoring, by the network monitoring device, another network
25 equipment in the network for receipt of a first response message which is
transmitted by the corresponding web server in response to the first
request message;
monitoring, by the network monitoring device, the network
equipment in the network for receipt of a second request. message, whiph
30 is transmitted by the user device in response to receipt of the first
response message;
monitoring, by the network monitoring device, the another network
equipment in the network for receipt of a second response message
which is transmitted by the corresponding web server in response to the
35 second request message;·
40
5 calculating, by a network monitoring device, a first delay parameter
D1, wherein the first delay parameter D1 is time elapsed between
detections of the first request message and the first response message;
calculating, by the network monitoring device, a second delay
parameter D2, wherein the second delay parameter D2 is time elapsed
10 between detections of the first response message and the second
request message;
calculating, by the network monitoring device, a third delay
parameter D3, wherein the third delay parameter D3 is time elapsed
between detections of the second request message and the second
15 request message; and
20
25
30
35
40
estimating the time, D5, elapsed between the user's first selection
on the web browser in the user device under control of the user to the
first bit received by the user device from the corresponding web server
according to an expression (1):