Installing and Administering OSI Transport Services

60 Chapter 1

HP OTS/9000 Resources

Building Temporary Administrative Preﬁxes

Building Temporary Administrative

Preﬁxes

In many cases, the examples above will not ﬁt the needs of many users.

This is because they are not government organizations, the company

does not reside in a country which has an NSAP authority, or the

company does not wish to pay the registration fees required to obtain an

NSAP space.

In cases like these, a network administrator can create a temporary

Administrative Preﬁx that their company may use as an interim solution

until a more permanent AP becomes available. The network

administrator must be sure to create a PAP format that can easily be

migrated to the permanent NSAP space, once it becomes available.

The ﬁrst two methods described create a unique NSAP space, and the

NSAP addresses may be used on open networks (that is, networks

connected to a public network). The last method, Local Format, does not

guarantee a unique NSAP space and should only be used when

connectivity to OSI networks outside the customer’s network is not

required.

Use an International Telephone Number

ISO allows NSAP spaces to be built that have an International

Telephone Number as their IDI value. This is known as the E.163

format. The AFI code to use is 43. The telephone number is encoded as

Binary Coded Decimal (BCD) into the IDI. Up to 12 digits may be used.

Any unused digits should be set to F (hexadecimal). The DSP portion,

and therefore the PAP, may be up to 13 octets in length.

Figure 1-18

43 Telephone

IDP

DSP

PAP

up to 13 octets