Hi I am still new and studying about networks have here address and mask but when I try it out on Packet tracer it gets me an invalid message. I cannot understand why this address are invalid.

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1 Answer 1


Invalid address is correct: is not a unicast but a multicast address from It cannot be used as an interface/source address.

For an interface in a private network you should use an address from RFC 1918 (,,

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