Cisco 6500 - Catalyst Series 10 Gigabit EN Interface Module Expansion Libro Blanco - Página 2

Navegue en línea o descargue pdf Libro Blanco para Hardware de red Cisco 6500 - Catalyst Series 10 Gigabit EN Interface Module Expansion. Cisco 6500 - Catalyst Series 10 Gigabit EN Interface Module Expansion 18 páginas. Distributed forwarding card 4 for ws-x68xx, ws-x69xx, and select ws-x67xx modules
También para Cisco 6500 - Catalyst Series 10 Gigabit EN Interface Module Expansion: Nota de instalación (14 páginas), Manual de soluciones (17 páginas), Nota de instalación (46 páginas), Libro Blanco (19 páginas), Descripción (1 páginas), Boletín de productos (6 páginas), Aviso (4 páginas), Ficha de datos (9 páginas), Ficha de datos (18 páginas), Manual de configuración (8 páginas), Nota de instalación (28 páginas), Manual de solución de problemas (11 páginas), Nota de instalación (18 páginas), Manual del usuario (17 páginas), Nota de instalación (24 páginas), Manual (19 páginas), Nota de instalación (36 páginas)

Cisco 6500 - Catalyst Series 10 Gigabit EN Interface Module Expansion Libro Blanco
Figure 1. CoS Field
®
Cisco Systems
supports the Inter-Switch Link (ISL) VLAN tagging option on selected Cisco Catalyst 6500 line cards. ISL is a Cisco proprietary
VLAN tagging option that also supports an inbuilt 3-bit CoS field just like the IEEE 802.1Q option mentioned earlier.
Type of Service
Built into every IP packet is an IP header, and like in the Ethernet example earlier, the IP header also contains a field that defines a priority value
for this packet. This field is the type-of-service (ToS) field. Unlike the CoS field, the ToS field is an 8-bit field. There are two ways to set a priority
value in the ToS field. One method, called IP precedence, uses the 3 most significant bits of the ToS field to yield eight priority values.
Differentiated Services Code Point (DSCP) is a second method for assigning a priority to an IP packet. DSCP uses the 6 most significant bits of the
ToS field to yield 64 different priority values. Figure 2 shows where the ToS bits are found in the IP header.
Figure 2. Reading IP Precedence and DSCP from the ToS Byte
© 2005 Cisco Systems, Inc. All rights reserved.
Important notices, privacy statements, and trademarks of Cisco Systems, Inc. can be found on cisco.com.
Page 2 of 18