Availability
Ultima is a NAT-PT implementation from BT Labs, it supplies a NAT-PT device with DNS, FTP and SIP ALG functionality. In this case, it was installed on FreeBSD 5.2 but should run on any version above FreeBSD 4.2. It cannot be directly downloaded from the Internet but is available by request on a case by case basis, below is a link the BTExact website highlighting the Ultima transitioning toolkit and other IPv6 activities at BT:
http://www.ipv6.btexact.com/activities/projects.html#ultima
Install and Configuration
Installation of Ultima takes place in two steps the basic device configuration and the http interface setup (which is rather less well documented). Installation of the device itself however is very straight forward, simply unzip the file into an appropriate directory and run the ultima_install program. Setup is via a text based interface which is both comprehensive and simple to use and can also be run at any time to reconfigure the device. It follows these basic steps.
| IPv4 interface | Specify IPv4 interface of device |
| IPv6 interface | Specify IPv6 Interface of device |
| IPv6 prefix | Specify IPv6 prefix of Ultima |
| Address Pool configuration | Configure IPv4 address pool, selecting this option allows the addition or removal of IPv4 addresses in the address pool and the addition or removal of static address mappings. At least one static mapping is required for the DNS |
| Lan/wan and DNS options |
Allows selection of lan or wan operating modes (basically Configures DNS ALG to allow IPv4 or IPv6 queries to get |
| http interface password |
Configures http interface password (see below) |
The http interface setup is rather more complicated and requires both Apache and openSSH ports to be installed onto the machine in addition to numerous other PERL modules. Afterwards, the interface package can be compiled and installed. Once installed, NAT-PT can be operated remotely via a browser. This was not attempted in our case.
Host Configuration
No major changes are needed for host configuration however the DNS options may need to be configured appropriately.
Issues
The installation procedure threw up several complications in that the supplied ‘ultima_NAT-PT.zip’ package cannot be opened in FreeBSD with the usual methods as the package seems to be windows based with MS Word documentation supplied as opposed to the usual README text files. To unzip the files, PKZip was used but they could easily be unzipped in Windows and transferred to UNIX. Additionally, the file permissions had to be changed as they were not set to be executable by any user by default (ultima_install, ultima, get_passwd, check_prefix, check_IPv4_address) so the device could not be configured or run.