XEDIA-TRAFFIC-MGMT-MIB Table View

This table is a 'flattened' version of a hierarchical class
trees that specify the bandwidth allocation for the CBQ
interfaces of the system.
          
Each tree is rooted at an interface. A class may either be a
leaf, meaning it has no children, or it may be an interior
class which has children. As packets are forwarded out an
interface, they are compared to the 'flow definition' of each
class down the tree until a matching leaf is found or until
all classes are traversed. Once a matching class is found, the
packet is transmitted or not based on the constraints
configured for the class, most importantly the allocated
bandwidth as identified by xtmClassRate. If no matching class
is found, the packet is dropped.
          
The 'flow definition' for a class can be defined based on
inclusive ranges of the following packet fields:
    o Source IP Address (or a domain name)
    o Destination IP Address (or a domain name)
    o Protocol above layer 3 (e.g., UDP, TCP, ICMP, etc.)
    o Source Port (which identifies service, e.g., FTP,
      Telnet, SMTP, etc.)
    o Destination Port
          
It is important that packets only match zero or one traffic
class. In order for this to be true, certain rules must be
enforced when classes are defined. Specifically, all 'sibling'
classes must be defined using the same criteria. Also,
children must use criteria not already specified by one of
their ancestors or they must specify a subrange of an already
specified criteria. Therefore, this tree would be legal:
          
interface 1
    subnet A
        protocol UDP
            port SNMP
        protocol TCP
    subnet B
          
But this tree would be illegal:
          
interface 2
    subnet A
        subnet B (illegal -- not subrange of parent)
    protocol TCP (illegal -- different criteria than sibling)