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Overally it was quite well described in the book, therefore only the two things are so far incomprehensible for me.

1) What does IoO mean?
2) Could you explain these strange floating-point numbers that I've circled?

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2 Answers 2

up vote 1 down vote accepted

Lo0 refers to a local network in this case, though more correctly, lo0 refers to loopback networks. The numbers you have . so-0/0/x and the decimal numbers seems to be the addressing scheme sonet uses but I'm having trouble finding the RFC for that.

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lo0 (it's 0, not O) is shortened loopback 0 - kind of virtual interface used mainly in routing and management. Those numbers are just last octets for p2p links as described in left bottom corner:

Note: all links use 10.0.x.y, only last octets are shown

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