SonicWALL TZ 190 Manuale Utente

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SonicOS Enhanced 4.0 Administrator Guide
To test the Telnet policy-based route, telnet to route-server.exodus.net and when logged in, 
issue the who command. It displays the IP address (or resolved FQDN) of the WAN IP address 
of the secondary WAN interface and not the primary WAN interface.
Advanced Routing Services (OSPF and RIP)
In addition to Policy Based Routing and RIP advertising, SonicOS Enhanced offers the option 
of enabling Advanced Routing Services (ARS). Advanced Routing Services provides full 
advertising and listening support for the Routing Information Protocol (RIPv1 - RFC1058) and 
(RIPv2 - RFC2453), and Open Shortest Path First (OSPFv2 – RFC2328). Advanced Routing 
Service should only be enabled by those environments requiring support for either or both of 
these dynamic routing protocols.
RIP and OSPF are Interior Gateway Protocols (IGP) that are both widely used by networks of 
various sizes to automate the process of route distribution. RIP is commonly used within 
smaller networks, while OSPF is used by larger networks, although network size should not be 
the only factor used to determine the appropriateness of one protocol over the other – network 
speed, interoperability requirements, and relative overall complexity, for example, should also 
be considered. RIPv1 and RIPv2 are both supported by ARS, the largest differences between 
the two being that RIPv2 supports VLSM (Variable Length Subnet Masks), authentication, and 
routing updates. The following table illustrates the major differences between RIPv1, RIPv2, 
and OSPFv2:
RIPv1
RIPv2
OSPFv2
Protocol metrics
Distance Vector
Distance Vector
Link State
Maximum Hops
15
15
Unlimited
Routing table 
updates
Full table 
broadcast 
periodically, 
slower 
convergence
Full table 
broadcast or 
multicast 
periodically, 
slower 
convergence
Link state 
advertisement 
multicasts, 
triggered by 
changes, fast 
convergence
Subnet Sizes 
Supported
Only class-based 
(a/b/c) subnets 
support
Class-based only
VLSM
Autonomous 
system topology
Indivisible and flat
Indivisible and flat
Area based, 
allowing for 
segmentation and 
aggregation