Question
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Topic
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redundancy at cable modem level
topic: redundancy in commercial environment
Problem: can’t find cable modem that provides at least two ethernet ports, each of which can connect to a different router.
application:
two isp. each has their own cable modem.
the output of each modem goes to two routers. Thus if a router fails, the other takes over. if an isp fails, the other takes over. one router and one isp can fail adn the system will run.problem:
the two most promising docsys 3.1 cable modems are arris sb8200 and the motorola mb 8600. My interpretation of the motorola specs is that the four ethernet ports can only go to one router.
Arris is not clear about their use of the two ports. My interpretation of their comments is that one can go to one router but the other can only go to another router if it has
been assigned (by the ISP) a different ip address than the original.In looking at that comment, I sense that they are right,, but can’t quite grasp it.
lets see. a packet handed to a router must be given an ip address by the router that is unique so that the isp can send it back to the correct router. maybe the way it works is that one router is not actually seen by either modem until falure. it then adopts the ip address of teh original.In this case it looks like arris is not allowing such a scheme to take place?
