Performance Degradation Causes

What causes performance problems when accessing applications over a network connection, or when transferring content from one location to another? The chain of technologies utilized communications networks can create significant performance problems for network reliant applications that are more complex than simple propagation delay phenomena. These include the following major performance limiters:

1.       System Latency, the total time for a full and complete data transaction over a given set of transport medium, expressed in milliseconds (ms)

a.       Propagation Delay= Total time required for the physical act of transporting a data bit over a given medium;

b.       Route Queuing= The cumulative delay created by routing and switching equipment in the full and complete data connection path;

c.       SATCOM Time Slotting= For Satellite communications networks where access is granted to Satellite transponders according to a revolving round-robin distribution of limited access. For example, 250ms of satellite access every 500ms;

d.       Data Modification Delay= The cumulative delay created by applications and devices which interact with the data stream such as encryptors, load balancers, error correctors, etc;

e.       End Point equipment saturation= the cumulative delay created by terminal end equipment such as servers and workstations which are near or at processor, memory, or disk capacity.

2.       Fragmentation, the bifurcation of a data packet due to packet size limitations

a.       Fragmentation from addition of overhead data

                                                               i.      VPN Encapsulation

                                                             ii.      Encryption

                                                            iii.      Packet signing and tagging

b.       IP Encapsulation

                                                               i.      SATCOM

                                                             ii.      Long Haul wireless

                                                            iii.      Cellular

                                                            iv.      Other Digital to Analog  to Digital conversions

c.       In-flight damage

3.       Application inefficiency

a.       “Circular” behaviors, such as communications paths which result in ultimately receiving or responding to self generated transmissions

b.       Unneeded updating cycles, such as full replication when differential is sufficient

c.       Inefficient network interfaces

                                                               i.      Poor retransmission handling, allowing multiple retransmission of the same content

                                                             ii.      Ineffective loss handling, creating locks or runs because of low level loss

                                                            iii.      Fixed rates and responses, unable to deal with dynamic transport conditions independently