Reduce Hop Count; Adjust Jitter Buffer Size - Nortel 1000 Description, Installation And Operation Manual

santa_clara_itg4 (10.3.2.7) 94 ms 97 ms 95 ms
The average rtt time on that link is about 40 ms; the one-way link delay is
about 20 ms, of which the circuit transmission and serialization delay are just
a few milliseconds. Most of this link's delay is caused by queueing. Looking
at Figure 26 on
is shaved off the delay budget.

Reduce hop count

End-to-end delay can be reduced significantly by reducing hop count,
especially on hops that traverse WAN links. Some the ways to reduce hop
count include the following:
• Attach the TLAN subnet directly to the WAN router.
• Improve meshing. Add links to help improve meshing; adding a link
from router1 to router4 in the previous Traceroute example might cause
the routing protocol to use that new link, thereby reducing the hop count
by two.
• Node reduction. Co-located nodes can be connected into one larger and
more powerful router.
These guidelines affect the whole intranet, as they affect network
architecture, design and policies and involves considering cost, political and
IP design issues. These topics are beyond the scope of this document.

Adjust jitter buffer size

The jitter buffer parameters directly affect end-to-end delay. Lowering the
voice playout settings decreases one-way delay, but the decrease comes at a
cost of allowing less waiting time for voice packets that arrive late. Refer to
"IP Trunk 3.01 (and later) DSP profile settings" on
on re-sizing the jitter buffer.
ITG engineering guidelines
page 180, if this link is upgraded to T1, approximately 19 ms
IP Trunk
page 218
Description, Installation, and Operation
Page 183 of 644
for guidelines