Routers MUST support Out-Of-Band (OOB) access. OOB access SHOULD provide the same functionality as in-band access. This access SHOULD implement access controls, to prevent unauthorized access.
This Out-Of-Band access will allow the NOC a way to access isolated routers during times when network access is not available.
Out-Of-Band access is an important management tool for the network administrator. It allows the access of equipment independent of the network connections. There are many ways to achieve this access. Whichever one is used it is important that the access is independent of the network connections. An example of Out-Of-Band access would be a serial port connected to a modem that provides dial up access to the router.
It is important that the OOB access provides the same functionality as in-band access. In-band access, or accessing equipment through the existing network connection, is limiting, because most of the time, administrators need to reach equipment to figure out why it is unreachable. In band access is still very important for configuring a router, and for troubleshooting more subtle problems.