I often have to log onto my work network to do little 5 or 10 minute tasks. It gets to be a headache running the cisco VPN client, connecting, disconnecting then having to do it again 20 minutes later.
I was wondering what the impact is to my home network and work network to leave it connected at all times?
Impact in terms of? We have several users that are connected via Cisco Client for Days and days at a time. My house is connected via a Cisco PIX 506 to a PIX 515, its connected 24/7.
I'm sure there are a few extra packets that dont need to be there, but unless you are on Dialup- there should not be that big of a hit in performance.
Oh, Unless your company does not do Split-Tunneling. (I think that is what it is called) Where you can connect to the VPN for VPN/Office Traffic, and then all other Internet Traffic uses the Local internet connection. If your company forces you to use their Internet Connection while connected to the VPN, your home network will probably sit a performance hit as all the traffic for the internet is now over the VPN.
I sometimes do similar to you, require short 15 minute sessions or work from home, sometimes hours apart.
Functionally, there is ZERO impact, as long as the configurations support the long logins. I frequently leave my work laptop connected to my Home LAN and logged into work via VPN, sometimes for a day or so. I have not noticed any particular issue. If I KNOW I wont need it for several hours I just log out and log in again when I need it, but this is just a preference to minimise my local traffic (we are still on a metered ADSL service here).
Practically, yes your machines consume resources at each end of the VPN tunnel, however as long as those resources are not in short supply, I can't see any obvious issue.
As stated, the only gotcha I would be aware of is that absent of split- tunneling, all your traffic goes into your corporate/business network. If this is not a concern (dedicated work machine), no problem. If this is a multi-use machine by you or your friends/ family, it brings up other concerns. These days, privacy is essential regardless of what someone does on the internet, and having a third party (especially one that pays you) see your online habits or mail is probably something with some risk and no reward. Using a legitimate example, what happens if you are doing research for side-business/ consulting gig? Who owns the intellectual property? A court would probably say your company if you were using their resources (network, internet, etc). Unless of course you own the business.....