Quality of Service guidelines
316 Avaya Application Solutions IP Telephony Deployment Guide
IEEE 802.1 p/Q
Figure 82: 802.1Q tag
The IEEE 802.1Q standard is a Layer 2 tagging method that adds 4 bytes to the Layer 2
Ethernet header. IEEE 802.1Q defines the open standard for VLAN tagging. Two bytes house
12 bits that are used to tag each frame with a VLAN identification number. The IEEE 802.1p
standard uses 3 of the remaining bits in the 802.1Q header to assign one of 8 different classes
of service. Communication Manager users can add the 802.1Q bytes and set the priority bits as
desired. Avaya suggests that a priority of 6 be used for both voice and signaling. The Avaya line
of data switches can switch frames with or without these VLAN headers, with no configuration
time spent. IEEE 802.1p and IEEE 802.1Q are OSI layer 2 solutions, and work on frames.
Because 802.1Q is a Layer 2 (Ethernet) standard, it only applies to the Ethernet header. At
every Layer 3 boundary (router hop), the Layer 2 header, including CoS parameters, is stripped
and replaced with a new header for the next link. Thus, 802.1Q does not enable end-to-end
QoS.
Содержание Application Solutions
Страница 1: ...Avaya Application Solutions IP Telephony Deployment Guide 555 245 600 Issue 3 4 1 June 2005 ...
Страница 20: ...About This Book 20 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 21: ...Issue 3 4 1 June 2005 21 Section 1 Avaya Application Solutions product guide ...
Страница 22: ...22 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 74: ...Avaya Application Solutions platforms 74 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 106: ...Call processing 106 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 124: ...Avaya LAN switching products 124 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 139: ...Issue 3 4 1 June 2005 139 Section 2 Deploying IP Telephony ...
Страница 140: ...140 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 186: ...Traffic engineering 186 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 204: ...Security 204 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 214: ...Voice quality network requirements 214 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 228: ...Avaya Integrated Management 228 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 239: ...Reliability Issue 3 4 1 June 2005 239 Figure 69 S8700 Media Server in a high reliability configuration ...
Страница 274: ...Reliability and Recovery 274 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 275: ...Issue 3 4 1 June 2005 275 Section 3 Getting the IP network ready for telephony ...
Страница 276: ...276 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 350: ...Implementing Communication Manager on a data network 350 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 356: ...Network recovery 356 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 366: ...Network assessment offer 366 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 367: ...Issue 3 4 1 June 2005 367 Appendixes ...
Страница 368: ...Appendixes 368 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 394: ...Access list 394 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 414: ...DHCP TFTP 414 Avaya Application Solutions IP Telephony Deployment Guide ...