Chapter 13
| Basic Administration Protocols
Connectivity Fault Management
– 475 –
◆
A Maintenance Level allows maintenance domains to be nested in a
hierarchical fashion, providing access to the specific network portions required
by each operator. Domains at lower levels may be either hidden or exposed to
operators managing domains at a higher level, allowing either course or fine
fault resolution.
◆
Maintenance End Points (MEPs) which provide full CFM access to a Service
Instance (i.e., a specific MA), and Maintenance Intermediate Points (MIPs) which
are passive entities that merely validate received CFM messages, or respond to
link trace and loop back requests. MIPs are the interconnection points that
make up all possible paths between the DSAPs within an MA, and may also
include interconnection points in lower-level domains if exposed by CFM
settings.
The following figure shows a single Maintenance Domain, with DSAPs located on
the domain boundary, and Internal Service Access Points (ISAPs) inside the domain
through which frames may pass between the DSAPs.
Figure 304: Single CFM Maintenance Domain
The figure below shows four maintenance associations contained within a
hierarchical structure of maintenance domains. At the innermost level, there are
two operator domains which include access points marked “O
1
” and “O
2
”
respectively. The users of these domains can see their respective MEPs as well as all
the MIPs within their domains. There is a service provider domain at the second
level in the hierarchy. From the service provider’s view, the access points marked
“P” are visible, and all access points within the operator domains have also been
made visible as MIPs according to common practice. And finally, there is a customer
domain at the top of the hierarchy. Users at this level can only see the access points
marked “C” on the outer domain boundary. Again, normal practice is to hide the
internal structure of the network from outsiders to reduce security risks.
Maintenance Domain
Bridge
DSAP
ISAP
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Страница 30: ...Figures 30 Figure 450 Showing RIP Peer Information 669 Figure 451 Resetting RIP Statistics 670 ...
Страница 34: ...Section I Getting Started 34 ...
Страница 48: ...Section II Web Configuration 48 Unicast Routing on page 651 ...
Страница 151: ...Chapter 4 Interface Configuration VLAN Trunking 151 Figure 69 Configuring VLAN Trunking ...
Страница 152: ...Chapter 4 Interface Configuration VLAN Trunking 152 ...
Страница 229: ...Chapter 8 Congestion Control Automatic Traffic Control 229 Figure 135 Configuring ATC Interface Attributes ...
Страница 230: ...Chapter 8 Congestion Control Automatic Traffic Control 230 ...
Страница 596: ...Chapter 14 Multicast Filtering Multicast VLAN Registration for IPv6 596 ...
Страница 620: ...Chapter 15 IP Configuration Setting the Switch s IP Address IP Version 6 620 ...
Страница 670: ...Chapter 18 Unicast Routing Configuring the Routing Information Protocol 670 Figure 451 Resetting RIP Statistics ...
Страница 672: ...Section III Appendices 672 ...
Страница 678: ...Appendix A Software Specifications Management Information Bases 678 ...
Страница 688: ...Appendix C License Statement GPL Code Statement Notification of Compliance 688 ...
Страница 696: ...Glossary 696 ...
Страница 706: ...GTL 2881 GTL 2882 E112016 ST R01 ...