What are the risks of having 2 IP ranges on 1 physical network?

[<gs () hallgarth middlesbrough sch uk>]

What are the risks of having 2 IP ranges on 1 physical network?

We have a fully switched network using HP ProCurve switches.  We currently use the 10.0.x.x IP range.  The Local 
Education Authority is giving us video conferencing equipment that uses the 10.48.x.x IP range to talk to other schools 
in the local area.  The physical link to the LEA is already in place but the only thing connected to it is a filtered 
proxy server, which is also connected to our network. 

As it stands at the moment to use the video conferencing equipment I would have to re-patch a network port to connect 
it directly to the LEA.  My boss wants me to connect the link to the LEA into our switches so the video conferencing 
equipment can be used anywhere anytime without me having to do anything.

What are the risks, if any, of doing this?

Thanks in advance.

Geoff Snowdon
Hall Garth School

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