A method and apparatus to provide encryption and authentication of a mini-packet
in a multiplexed real time protocol (RTP) payload. Mini-packets are assembled into
a payload wherein each mini-packet includes an associated mini-header for ensuring
proper processing of each mini-packet. Padding is added to mini-packets when the
mini-packets are encrypted to insure each mini-packet is an integral multiple of
a predetermined block size. Padding for each mini-packet is determined according
to p=n-;k*floor((n-;1)/k), wherein p is the amount of padding added to each mini-packet,
n is the actual data size, and k is the block size. The padding added to the data
for each packet comprises p-;1 units of padding and a final padding unit for indicating
the amount of padding. An authenticator may also be added to each mini-packet.
A length indicator is set in each mini-header for indicating a total length of
the mini-packet including the authenticator. The authenticator may then be removed
based upon knowing a type of authentication used for generating the authenticator.
