RFC 2627 (rfc2627) - Page 2 of 23
Key Management for Multicast: Issues and Architectures
Alternative Format: Original Text Document
RFC 2627 Key Management for Multicast June 1999
multicast communication being that multiple receivers simultaneously
get the same transmission. Thus the problem is enabling each user to
determine/obtain the same net key without permitting unauthorized
parties to do likewise (initializing the multicast group) and
securely rekeying the users of the multicast group when necessary.
At first glance, this may not appear to be any different than current
key management scenarios. This paper will show, however, that future
multicast scenarios will have very divergent and dynamically changing
requirements which will make it very challenging from a key
management perspective to address.
2.0 INTRODUCTION
The networks of the future will be able to support gigabit bandwidths
for individual users, to large groups of users. These users will
possess various quality of service options and multimedia
applications that include video, voice, and data, all on the same
network backbone. The desire to create small groups of users all
interconnected and capable of communicating with each other, but who
are securely isolated from all other users on the network is being
expressed strongly by users in a variety of communities.
The key management infrastructure must support bandwidths ranging
from kilobits/second to gigabits/second, handle a range of multicast
group sizes, and be flexible enough for example to handle such
communications environments as wireless and mobile technologies. In
addition to these performance and communications requirements, the
security requirements of different scenarios are also wide ranging.
It is required that users can be added and removed securely and
efficiently, both individually and in bulk. The system must be
resistant to compromise, insofar as users who have been dropped
should not be able to read any subsequent traffic, even if they share
their secret information. The costs we seek to minimize are time
required for setup, storage space for each end user, and total number
of transmissions required for setup, rekey and maintenance. It is
also envisioned that any proposed multicast security mechanisms will
be implemented no lower than any layer with the characteristics of
the network layer of the protocol stack. Bandwidth efficiency for
any key management system must also be considered. The trade-off
between security and performance of the entire multicast session
establishment will be discussed in further detail later in this
document.
Wallner, et al. Informational