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Management and BITS ports on an ASR1002



We recently purchased a Cisco ASR1002 router with four on-board Gigabit SFP-style Ethernet ports. However, when I do a "show ip interface brief", I see that there's an extra Gigabit Ethernet port. See the last interface in the following output:

ASR_1002_router#sh ip int b

Interface                         IP-Address       OK?     Method Status          Protocol

GigabitEthernet0/0/0       unassigned      YES  manual     down                down

GigabitEthernet0/0/1       unassigned      YES  manual     down                down

GigabitEthernet0/0/2       unassigned      YES  manual     down                down

GigabitEthernet0/0/3       unassigned      YES  manual     down                down

GigabitEthernet0            unassigned       YES  unset    administratively down down

On the router itself, in addition to the four Ethernet SFP ports, there are four additional RJ-45 ports. They're labeled "BITS", "MGMT", "CON", and "AUX". I know what the Con and Aux ports are, but what are the Bits and Mgmt ports? And is one of them the Gigabit Ethernet interface that I see listed at the bottom of the output? And if it is, is there anything special about it, or is it just another routed Ethernet port? Can I do something special with it, like out-of-line managment?


1 Reply 1

Collin Clark

The BITS port provide connections for an external synchronization source for establishing precise frequency control at multiple network nodes, if required for your application. The RSP card contains a synchronous equipment timing source (SETS) that can receive a frequency reference from an external BITS timing interface or from a clock signal recovered from any incoming Gigabit Ethernet or 10-Gigabit Ethernet interface. The RSP SETS circuit filters the received timing signal and uses it to drive outgoing Ethernet interfaces.

The BITS input can be T1, E1 or 64K 4/. The BITS output can be T1, E1 or 6.312M 5/.

Mgmt is for out-of-band management and that should be the GigabitEthernet0 interface you see at the end.

Hope it helps.

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