Cisco DNCS System Release 2.7 3.7 4.2 Références techniques
4011319 Rev C
3
Former Network Architecture (Mirror QAMs)
Former Network Architecture (Mirror QAMs)
Background
In earlier system releases, MSOs use "mirror" QAMs to pass unmodified PSIP to
DHCTs, as shown in the following diagram.
DHCTs, as shown in the following diagram.
The major disadvantage of this configuration is that it required two QAM
modulators for each service or set of services. One QAM actually passed the content
and the PSIP to the DHCTs; the second ("mirror") QAMs provided tuning
information to the DHCTs.
modulators for each service or set of services. One QAM actually passed the content
and the PSIP to the DHCTs; the second ("mirror") QAMs provided tuning
information to the DHCTs.