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| – |
agent
advertisements transmitted every second by
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mobility
agents (extension of ICMP router
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advertisement),
serves as a “beacon” for cell selection
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| – |
alternatively,
mobile can issue agent solicitation
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(extension
of ICMP router solicitation) when no
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advertisements
received
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foreign
agents can:
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n |
be
too busy for more clients (but still send out advertisements)
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n |
describe
what encapsulation they offer
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n |
require
registration via an advertised care-of address (even if
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mobile
has co-located care-of address)
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| – |
service
advertisements not authenticated
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