Specifications

4-6
Cisco XR 12000 Series Router SIP and SPA Software Configuration Guide, Release 3.2
Release 3.2, OL-6396-01, Rev.A1 January 9, 2006
Chapter 4 Configuring Ethernet SPAs on Cisco IOS XR Software
Configuration Tasks
• Flow Control on Ethernet Interfaces, page 4-7
• MAC Address, page 4-8
• 802.1Q VLAN, page 4-8
• VRRP, page 4-8
• HSRP, page 4-8
Ethernet Technology Overview
Ethernet was developed in the mid-1970s as a 10-Mbps networking protocol operating over a heavy coax
cable.
Today, although many networks have migrated to Fast Ethernet (100 Mbps), Gigabit Ethernet
(1000 Mbps), and 10-Gigabit Ethernet (10 Gbps), 10-Mbps Ethernet is still in widespread use and forms
the basis of most networks.
Ethernet is defined by the IEEE 802.3 international standard. It enables the connection of up to 1024
nodes over coax, twisted-pair, or fiber-optic cable.
Default Configuration Values
When an interface is enabled on an Ethernet SPA and associated SIP, the following default interface
configuration parameters are present. See Table 4-1.
Note You must specifically configure the shutdown command to bring an interface administratively down.
The interface default is no shutdown. When a SPA and SIP are first inserted into the router, if there is
no established preconfiguration for it, the configuration manager adds a shutdown item to its
configuration. This shutdown can be removed only by entering the no shutdown command.
Gigabit Ethernet Protocol Standards Overview
IEEE 802.3ab 1000BASE-T Gigabit Ethernet
The IEEE 802.3ab protocol standards, or Gigabit Ethernet over copper (also known as 1000BaseT) is an
extension of the existing Fast Ethernet standard. It specifies Gigabit Ethernet operation over the
Category 5e/6 cabling systems already installed, making it a highly cost-effective solution. As a result,
most copper-based environments that run Fast Ethernet can also run Gigabit Ethernet over the existing
network infrastructure in order to dramatically boost network performance for demanding applications.
Table 4-1 Ethernet SPA Default Configuration Values
Parameter Configuration File Entry Default Value
MAC Accounting mac-accounting off
Flow Control off
MTU mtu 1514 for normal interfaces, 1518 for 802.1Q
VLAN
MAC Address mac address Hardware burned in address (BIA)