The School of Informatics has some 40 or so different IP subnets in use.
Each of these subnets serves a particular purpose but, for users in the Informatics Forum, the five most important subnets are:
| Subnet | Purpose |
|---|---|
| 129.215.24.0/22 2001:630:3c1:24::/64 |
DICE desktop machines |
| 129.215.90.0/23 2001:630:3c1:90::/64 |
Self-managed machines using dynamically-assigned IP addresses |
| 129.215.164.0/23 2001:630:3c1:164::/64 |
Self-managed machines using fixed IP addresses |
| 129.215.197.0/24 2001:630:3c1:197::/64 |
Self-managed machines using fixed IP addresses |
| 129.215.224.0/24 | Windows managed desktop machines |
(Note: the fact that we have two subnets for 'Self-managed machines using fixed IP addresses' is just because of the way addresses have been progressively allocated. Logically, these two subnets serve exactly the same purpose.)
Each of these subnets is carried on a particular VLAN - i.e. a virtual 'piece of ethernet'. The mapping of the above subnets to VLANs is:
| Subnet | VLAN name | VLAN number |
|---|---|---|
| 129.215.24.0/22 2001:630:3c1:24::/64 |
DICE | 24 |
| 129.215.90.0/23 2001:630:3c1:90::/64 |
DHCP | 90 |
| 129.215.164.0/23 2001:630:3c1:164::/64 |
SM164 | 164 |
| 129.215.197.0/24 2001:630:3c1:197::/64 |
SM197 | 197 |
| 129.215.224.0/24 | MDT | 224 |
In addition, VLAN 952 - called 'phones' - is used to carry the traffic to and from VoIP telephones in the Forum.
All of this means that, for example, should you want to use a laptop in the Informatics Forum on the 129.215.90.0/23 subnet, that laptop must be connected to a network port which has been configured to be on the 'DHCP' VLAN.