/32 Mask

[obaidmushtaq]

Dear All,

Could anyone please explain me the use of /32 mask? When I connect to the Internet via my Mobile phone connected to Laptop (GPRS/EDGE), the following IP with /32 mask gets assigned:

PPP adapter GPRS:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
Physical Address. . . . . . . . . : 00-53-45-00-00-00
Dhcp Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 10.189.10.173
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 10.189.10.173

Also the default gateway is same as my own address. Can anyone shed some light on the two points.

Kind Regards,

Obaid

[Big Evil]

Can you reset the ip address?
Also i see the DCHP is not enabled.

[obaidmushtaq]

Hello Big Evil,

Here is the new IP assigned on my GPRS Dialup interface:

PPP adapter GPRS:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
Physical Address. . . . . . . . . : 00-53-45-00-00-00
Dhcp Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 10.189.21.157
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 10.189.21.157
DNS Servers . . . . . . . . . . . : 221.132.112.8
202.163.96.3
NetBIOS over Tcpip. . . . . . . . : Disabled

One thing I must tell you that everything is working fine. I mean the Internet via GPRS. I was curious about the /32 mask and the gateway address being the same as my IP@.

BR,

Obaid

[Big Evil]

I am thinking that the /32 (255.255.255.255) would define a network of only one device.
Also to the ip address and the default gateway being the same. Just one route.

[obaidmushtaq]

A network of one host, OK but how does it communicate with the hosts on the Internet?

I am confused about this /32 concept. Can anyone please tell me the use ?

BR,

Obaid

[lammle]

This is a weird output from PPP and it is never explained well.

PPP, since it has to be point to point, places a route in your routing table of /32 meaning it is a host entry. "how do I get to this host?". Which is your next hop router.

It really is an entry you can ignore. PPP places that in your routing table by default.

Cheers!
Todd

[Frebius]

Kind of an old post but so sorry but, a /32 mask is perfect when assigning loopback addresses as it really saves space. You can advertise the entire /24 address block and the have individual /32 addresses assigned to your loopbacks :)

[Fuzz]

That's interesting actually because, technically, a subnet mask of /32 would define a single network address with no hosts. If a /31 defines a network address and it's broadcast address only, that would be the same as having one host (although not addressable). What the /32 netmask is saying is 'this host only'.

Take a look at the routing table of a PC running Windows, netstat -r (or route print) will show you examples of /32 netmasks, and they are used to either define the host loopback address (turning the host address into 127.0.0.1) or to define broadcast addresses for the local LAN. Notice that for the latter, the default gateway is the same as the host address. As it is a local broadcast, no gateway is needed.

[pm123]

hi all,
there is a very basic thing which what i want to ask:--
difference between the switch, hub, repeater & bridge and especially with reference to the bandwidth.
thnx

[Fuzz]

Wikipedia & google are your friends

http://en.wikipedia.org/wiki/Computer_networking_device

http://www.google.co.uk/search?hl=en&q=network+devices&meta=

[pm123]

thanks for your reply