About routers, Routers – Grass Valley NV9000-SE v.3.0 User Manual
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Rev 3.0 • 25 Mar 10
7. Routers
About Routers
About Routers
A router is a switching matrix that enables you to connect any input to any output dynamically, rap-
idly making new connections. A switching matrix allows fanout, but not mixing. That is, an input
(a source) can be directed to multiple outputs (destinations). However, several inputs cannot be sent
to a single output.
Here is an example of a 4 × 3 switching matrix:
The following example shows input 3 connected to outputs 1 and 2, and input 4 connected to
output 3:
In general, a matrix for switching inputs and outputs is called a crosspoint matrix because signals
switch at the crosspoint from input to output. A routing system is a set of crosspoint matrices.
Using routers, different types of signals can be switched: video, HD, SD, AES, analog audio, time-
code, machine control, and others. Different routers support different signal types.
In a router, each signal type has its own crosspoint matrix. If you think of a crosspoint matrix as a
3-D representation, each signal is a separate crosspoint matrix, and each matrix exists as a separate
level. This concept is extremely important to remember when configuring routers in the NV9000-
SE.
The following is an example of how each crosspoint matrix can be considered a “level” of a 3-D
matrix:
Figure 7-1. Crosspoint Matrices as Levels
For more information on levels, see
1
2
3
4
1
2
3
Output
Input
Ena
An X marks each point (a crosspoint)
in the matrix. At the most basic level,
each crosspoint has an enable circuit
that permits the signal to connect
from the input to the output.
Some routers do extensive signal
processing. For such routers, this
diagram is overly simplified.
1
2
3
4
1
2
3
(Circles represent connections.)
HD
AES1/2
AES3/4
TC