Nortel ISDN Signaling Link, Описание, установка и эксплуатация

Страница: 114 / 380

Page 114 of 378 ITG Engineering Guidelines
553-3001-202 Standard 1.00 April 2000
Measure intranet QoS
You can measure end-to-end delay and error characteristics of the current
state of the intranet. These measurements help you set acceptable QoS
standards when using the corporate intranet to transmit voice services.
Measure end-to-end network delay
The basic tool used in IP networks to measure end-to-end network delay is
the
SLQJ program. SLQJ takes a delay sample by sending an ICMP packet
from the host of the
SLQJ program to a destination server. SLQJ then waits
for the packet to make a round trip. The output of
SLQJ is like the following:
5LFKDUGVRQ SLQJ V VDQWDBFODUDBLWJ
3,1* VDQWDBFODUD GDWD E\WHV
E\WHV IURP LFPSBVHT WWO WLPH PV
E\WHV IURP LFPSBVHT WWO WLPH PV
E\WHV IURP LFPSBVHT WWO WLPH PV
E\WHV IURP LFPSBVHT WWO WLPH PV
E\WHV IURP LFPSBVHT WWO WLPH PV
E\WHV IURP LFPSBVHT WWO WLPH PV
E\WHV IURP LFPSBVHT WWO WLPH PV
E\WHV IURP LFPSBVHT WWO WLPH PV
A"
5LFKDUGVRQ 3,1* 6WDWLVWLFV
SDFNHWV WUDQVPLWWHG SDFNHWV UHFHLYHG SDFNHW ORVV
URXQGWULS PV PLQDYJPD[
The time field displays the round trip time (rtt).
So that the delay sample results match what the ITG node can experience, the
SLQJ host must be on a working LAN segment attached to the router
intended to support the ITG node. The selection of destination host is just as
important, following these same guidelines for the source host.
The size of the
SLQJ probe packets must be set to 60 bytes to approximate
the size of probe packets sent by the ITG that are used in determining when
new calls need to fall back.