Comparing SLiRP vs Alternatives

Advantages of SLiRP over term

• Only needs compilation on one side of the link (the remote side)
• No need to "port" (termify) software
• Can be used by non-UNIX users (DOS/Win/Mac/etc.)
• Is more secure
• Is easier to use by multiple users (since you're using the kernel's networking code, which is already multi-user (well, should be...))

Advantages of term over SLiRP

• Compression (this is planned in SLiRP. Infact, I plan to "borrow" the compression code from term :)
• Term has more complete emulation (see below)
• Tupload (working on it)

Advantages of SLiRP over real (C)SLIP/PPP accounts

• No need to have your own IP address. This can be useful if you are running out of IP's (as the whole Internet is)
• You can connect your whole LAN to the 'Net without even needing one IP address. eg: If you have a LAN of 3 PC's at home, just route all packets to the host that has the modem, have it forward IP packets and route all packets over SLiRP. Easy!
• Speed. Depending on your situation, the speed improvement can be significant. In real (C)SLIP/PPP connections, the IP packets are sent to and from the remote host directly, whereas with SLiRP, it's the remote-host which takes care of all this, SLiRP only (tries to) makes sure the modem is used to full capacity. It's sorta like a "funneling" effect, as long as the remote-host has a fast connection to the 'Net, it'll keep enough data buffered to keep SLiRP happy.
• Security. No need to worry about IP address spoofing, ICMP attacks, etc. You dictate how much access to grant outside users to your home machine, via port redirection. (Watch those X redirections! Make sure you have access control enabled, or you can be snooped with the greatest of ease)

Advantages of real (C)SLIP/PPP over SLiRP

• You get your own IP address. This lets other people ftp into your home machine without needing to use a weird port number, etc.
• All programs will work. In SLiRP, some programs may not work because you do not have your own IP address, so some programs need to be "emulated".
• Speed. Again, depending on your situation, speed may be better than with SLiRP. (eg: because SLiRP will be run on a machine, competing with other processes, it will slow down on high loads, whereas with real (C)SLIP/PPP, the remote-host usually only acts as a "router" so it won't be prone to high loads)