gif tunnel overhead

[Lowell Gilbert]

FreeBSD MailingLists <freebsd.ml at gmail.com> writes:

> about how much (what percent) bandwidth overhead should I expect if I
> connect two hosts using a UNENCRYPTED gif tunnel over a 2Mbps
> connection?

It depends on the kind of packets you're sending.  As a corollary to
that, the overhead will probably *not* be symmetrical (in both
directions).  It also depends on how the tunnel is configured.

For maximum-size regular Ethernet packets with IPv4 over IPv4, figure
a couple of percent of overhead; for minimum-size IP packets, it will
be over 30%.  The latter case probably isn't a problem, though,
because it's unusual to fill a symmetrical-bandwidth link with
minimum-size packets.