Address space allocation:

Introduction

This document describes the IP address plan we will use for this set of workshop exercises.

Wherever possible the plan tries to replicate real life as closely as possible.

The IPv4 address space used in these exercises is from subnets of 100.64.0.0/10 which is an IPv4 Shared Address block. It must not be routed on the Internet.

Note that 2001:DB8::/32 is the IPv6 Documentation Address block. It must not be routed on the Internet.

And finally note that the 2001:10::/28 address block has been listed in the IANA special registry for future use. It must not be routed on the Internet.

If using these labs as inspiration for your own infrastructure design, please replace all instances of private, documentation, and unassigned address space with your own address blocks.

IP Address Plan

End-Site networks

Typically end-site networks (such as Universities, Colleges, etc) will receive a public IPv6 /48 and a very small public IPv4 block from their network operator (be it an ISP and/or their NREN)

We will use an IPv4 /24 for these exercises, reflecting the fact that in reality an end-site organisation will use a large private block like a /16 internally, NATed out into a small public IPv4 block like the /24 we are using here. (The private IPv4 address space is included for completeness, but is not used in these exercises as we are focusing on the BGP and traffic engineering needs of Universities and NRENs.)

Subnetting for each Group

Each group will then further partition their space as follows (you will need to replace the ‘X’ with your group number):

Point-to-Point Link Addressing within a Group

Prefixes for point-to-point links will be of length /30 for IPv4 and /127 for IPv6 (we will adopt the recommendations of RFC6164 for IPv6 inter-router links where we reserve a /64 for the link but subnet it as a /127):

Loopback Addressing

Router loopback address subnet masks will be /32 for IPv4 and /128 for IPv6:

Point-to-Point Link Addressing – ISP to Group

The point-to-point link addresses from the ISPs to the End-sites are listed next. Note that the ISP will get the low address, and the end-site gets the high address in the subnet.

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