OSPF: non-broadcast multiaccess (point-to-multipoint type)

RFC2328 compliant (point-to-multipoint type) 1. RFC2328 compliant mode. 2. No DR and BDR is/are needed. 3. Multicast OSPF hello packet is sent to discover neighbours. 4. Typically for partial mesh or star topology.   Debug output of 2651-4 2651-4# *MarĀ  3 11:26:39.841: OSPF: Interface Serial0/0.301 going Up *MarĀ  3 11:26:39.841: OSPF: Send hello to … Continue reading OSPF: non-broadcast multiaccess (point-to-multipoint type)


OSPF: non-broadcast multaccess network (broadcast type)

OSPF using broadcast network type over NBMA 1. Uses multicast (, AllSPFRouter multicast) to automatically discover neighbours, no need to use neighbor command for OSPF router to send hello via unicast. 2. Cisco mode. (non RFC2328-compliant) 3. DR and BDR will be elected. 4. Typically full mesh or partial mesh topology. 5. Hello is sent … Continue reading OSPF: non-broadcast multaccess network (broadcast type)

OSPF: non-broadcast multiaccess network (non-broadcast type)

OSPF network types 1. Point-to-point: Network between a pair of routers. 2. Broadcast multiaccess: If you connect the routers to a switch, the switch is broadcast capable. OSPF over EoMPLS behaves the same as broadcast multiaccess, OSPF routers do not know the existence of EoMPLS at all. DR is required, BDR can be elected if … Continue reading OSPF: non-broadcast multiaccess network (non-broadcast type)

Non-broadcast multi-access network

Hub and spoke connectivity over frame relay (NBMA)   1. Multipoint NBMA allows one subnet to be used by hub and spoke routers. 2. In contrast to multipoint, point to point link is a subnet hence consumes more IP subnets. 3. Communication between spoke routers can be established via hub router. Both the spoke routers … Continue reading Non-broadcast multi-access network

Wireless: From Central office to Branch office over Frame relay

Introduction The enterprise has a 64kbps frame relay link that links central office and branch office together. The wireless lan controller (WLC: cisco 2125) is deployed at central office, and two lightweight access points (LAP) are deployed at branch office.(Not all configuration is configured, the main objective is to test H-REAP over a frame-relay wan … Continue reading Wireless: From Central office to Branch office over Frame relay

Configuring a frame relay switch (or frame relay cloud)

Configuring a frame relay switch (or frame relay cloud) by Cyrus Lok on Sunday, September 5, 2010 at 9:33pm Ever since I have started out cisco networking career last year I have only learned how to configure routers to connect the frame relay cloud, nothing and not a single thing was mentioned on how to … Continue reading Configuring a frame relay switch (or frame relay cloud)