From what Sago said I think you can find back these numbers.
Bitmasks work like these:
1 1 1 (in binary)
4+2+1=7 (in decimal)
5 = 1 0 1 => only HTTP download
3 = 0 1 1 => sv_dlURL ignored
7 = 1 1 1 => http & UDP disabled
1 = 0 0 1 => ... at least I can say http download work, and I suppose UDP too.
0 = 0 0 0 => ... Oh crap I abandon