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Section about area structure, other chapter headings.

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LEdoian 1 year ago
parent 1f2758edce
commit 66eb64b613

@ -229,3 +229,32 @@ system.
\XXX{netsplit, multi links w/ same and diff costs, v2 vs v3, mixed segments,
multiple prefixes. napsat na kolejích s gennetem..}
\section{Area structure}
It is also worth to consider the expected size and structure of an OSPF areas
where Birdvisu might run. While it is up to the administrator and they may be
very creative, there are some limits to such creativity.
The largest system which can be spanned by a single OSPF instance is the whole
autonomous system (AS). The largest ASes only have about several hundred
thousand routers\cite{as-topologies}. The average degree also seems to be rather
low.
We can derive another limit from IPv4 address allocations. A /8 block (i.e.
Class A) has 16 777 216 addresses. Very few ISP would be assigned such a large
block, but they might be using the 10.0.0.0/8 private block. Even if an ISP
wants to use all those addresses, majority of them will likely not be assigned
to routers, but to some end devices that actually provide \uv{useful} services.
Those devices are also likely to be grouped into non-trivial networks, thus
reducing the number of vertices (i.e. routers and networks) in the OSPF
topology. (While IPv6 allocates many more addresses, we assume that the overall
topology will not be different from the IPv4 one.)
It is probably not practical to have a single OSPF area span all the routers in
a large AS, since any link state change results in an LSA being flooded
throughout the area.
While we cannot be sure about particular administrative decisions, given the
observations above, we expect that a single area contains at most few thousand
vertices and probably much less than that.

@ -0,0 +1 @@
\chapter{Design}\label{ch:design}

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\chapter{Usage}\label{ch:usage}

@ -0,0 +1 @@
\chapter{Evaluation}\label{ch:evaluation}

@ -12,6 +12,9 @@
\include{intro}
\include{chap01}
\include{chap02}
\include{chap03}
\include{chap04}
\include{chap05}
\include{epilog}

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