Multiservice Networking, IPX Networking, and Security - CCIE Routing and Switching Exam Certification Guide - page 554

SS7 Components Figure 12-4

SSP STP STP

SCP

SSP STP STP

SCP

STP

SSP

STP

SSP

Tools for Better Bandwidth Utilization in VoIP Networks
Cisco provides different QoS tools that you must use on edge and backbone routers to support
VoIP networks. Edge routers are concerned with packet classification, admission control,
bandwidth management, and queuing. Backbone routers perform high-speed switching and
transport, congestion management, and queue management.

The following tools are valuable for VoIP networks:
•

Multilink PPP with Interleaving —Allows large packets to be multilink-encapsulated
and fragmented into smaller packets.

•

RTP Header Compression —Compresses IP/UDP/RTP headers from 40 bytes to 2/4
bytes.

•

Weighted Fair Queuing (WFQ) —Queues packets based on the arrival time of the last
bit rather than the first bit, which ensures that applications that use large packets cannot
unfairly monopolize the bandwidth. Class Based-WFQ (CB-WFQ) can be configured to
look at the IP precedence bits of IP packets.

Securit This section covers the following exam security blueprint topics:
•

Authentication, authorization, and accounting (AAA)

•

TAC ACS