netmask question

[Pollywog <pollywog@shadypond.com>]

If this is the wrong place to ask this question, just let me know.

I installed a script that configures ipchains for me, and it gives me some
error messages about an incorrect netmask, but the author of the script
told me the error messages are in error because his script "groks" the
netmask from 'ifconfig'.

I did 'ifconfig' and I get something interesting for ppp0.
Why does ppp0 not have the netmask 255.255.255.0 just as my network card
has?

ppp0      Link encap:Point-to-Point Protocol  
          inet addr:209.209.28.252  P-t-P:209.209.28.245 
Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
          RX packets:21 errors:1 dropped:0 overruns:0 frame:1
          TX packets:24 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:10 

eth0      Link encap:Ethernet  HWaddr 00:60:97:3A:DD:BF  
          inet addr:192.168.1.1  Bcast:192.168.1.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:490 errors:0 dropped:0 overruns:0 frame:0
          TX packets:954 errors:0 dropped:0 overruns:0 carrier:0
          collisions:23 txqueuelen:100 
          Interrupt:15 Base address:0xef00 

thanks

--
Andrew