During transmission through heterogeneous networks, it may be necessary to force data to conform to a network's local conventions. For example, it may be required that a CR be followed either by LF, making a CRLF, or by <null>, if the CR is to stand alone). Such transformations are reversed, when the message exits that network.
When crossing network boundaries, the message should be treated as passing through two modules. It will enter the first module containing whatever network-specific transformations that were necessary to permit migration through the "current" network. It then passes through the modules:
The "current" network's idiosyncracies are removed and the message is returned to the canonical form specified in this standard.
The "next" network's local idiosyncracies are imposed on the message.
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From ==> | Remove Net-A |
Net-A | idiosyncracies |
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\/
Conformance
with standard
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\/
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| Impose Net-B | ==> To
| idiosyncracies | Net-B
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