Specifications

OmniAccess 5510 USG - Release Notes
September 2010
Multicast Protocols
Multicast is an efficient way to deliver traffic from one sender to many potential receivers.
PIM-SM
Protocol Independent Multicast (PIM) protocols route multicast packets to multicast groups. PIM is
protocol independent because it can leverage whichever unicast routing protocol is used to populate
unicast routing table.
PIM-SM is a multicast routing protocol that can use the underlying unicast routing information base
or a separate multicast-capable routing information base. It builds unidirectional shared trees rooted at
a RP per group, and optionally creates shortest-path trees per source. It defines a Rendezvous Point
(RP) that is then used as a registration point to facilitate the proper routing of packets.
IGMP v1, v2
IGMP (Internet Group Management Protocol) is used by IP hosts to report their multicast group
memberships to any immediately-neighboring multicast routers. Multicast routers use IGMP to learn
which groups have members on each of their attached physical networks.
The OmniAccess 5510 USG supports IGMPv2 as default IGMP version. As IGMPv2 is backward
compatible, it works well with IGMPv1 host as well.
Network Services
DHCP Server
DHCP is a protocol used to configure an IP device connected in a network. The configuration
parameters include - IP address, DNS information, default route and so on. With dynamic addressing,
a device can have a different set of network parameter values every time it connects to the network. In
some systems, the device's IP address can even change while it is still connected. DHCP also supports
a mix of static and dynamic IP addresses.
Dynamic host configuration simplifies network administration because the software keeps track of
host configuration rather than requiring an administrator to manage the task. This means that a new
network device can be added to a network without the hassle of manually configuring it. Many ISPs
(Internet Service Providers) use dynamic IP addressing for dial-up users. The DHCP server in
OmniAccess 5510 USG provides DHCP clients with an IP address along with other network and boot
information, based on the DHCP request received from the client.
DHCP Relay
Alcatel-Lucent DHCP relay feature eliminates the need for a DHCP server on every LAN, because
DHCP requests can be relayed to a single remote DHCP server. DHCP Relay Agent acts as an
intermediary between clients and servers by listening for client DHCP broadcast requests and
forwarding them on to the server. In addition, the Relay Agent receives the server's response and
passes the response back to the client. The relay agent allows the client and server to reside on
different subnets. Enabling DHCP server on OmniAccess 5510 USG automatically disables DHCP
relay.
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