| As I pointed out in a previous article, | | | | SCM network. Firewalls at each end allowed |
| Supply Chain Management (SCM) is a complex | | | | each company to control its own security. The |
| animal. The key to a successful SCM | | | | frame relay network was vulnerable to |
| implementation is a clear understanding of | | | | external monitoring at very few points, and |
| the business objectives and business | | | | the relationship of PVC traffic to specific |
| requirements of the company the SCM primarily | | | | customer required specific network design |
| supports. This often includes a number of | | | | information.Frame relay offered the ability |
| legacy systems which need to be integrated | | | | to have a disaster recovery site support |
| into the solution. From this will come the | | | | multiple locations. PVC between the disaster |
| technical objectives to be met and the | | | | location and other locations could be defined |
| technical requirements that frame the | | | | in the configuration, allowing dynamic |
| solution. Only then will the commmunication | | | | implementation of the disaster recovery |
| requirements for bandwidth capacity, | | | | network.As a circuit protocol, frame relay |
| reliability, resiliancy, latency, security, | | | | functions independent of other protocols. |
| and expandability be meaningful.Here's just 2 | | | | This segmentation allowed IPX, IP, SNA, and |
| such technical aspects.....Frame RelayFrame | | | | other system communications protocols to be |
| relay initially had several advantages over | | | | implemented over the same paths. If desired, |
| the alternative solutions for SCM and other | | | | each of these could have its own PVC and |
| multi site and multi company communications | | | | bandwidth, or they could all operate over a |
| networks.The first advantage was with circuit | | | | common path. Finally, the bandwidth and |
| costs. For a multi site network, the | | | | performance could be established specifically |
| traditional approach was a large number of | | | | to site pairs on a PVC basis.For a vendor |
| point to point circuits. Each circuit | | | | that participated in multiple SCM networks, |
| required a router port, a CSU, and often a | | | | frame relay represented real cost savings. |
| circuit monitoring module. With milage based | | | | Instead of a new circuit for each network, a |
| pricing, each circuit represented a | | | | PVC could be established. Instead of 6 week |
| significant recurring cost on top of the | | | | circuit installation delays, service could be |
| initial hardware costs. Router sizing was | | | | established in hours.----So why the past |
| often a factor of ports supported rather than | | | | tense? The advantages of frame relay are now |
| performance capability.Frame relay exchanged | | | | achieved via the Internet. The timeframes for |
| the point to point circuit costs with an | | | | implementation have been reduced from hours |
| access circuit, typically at less than 1/10th | | | | to minutes. Encryption has advanced beyond |
| of the cost. With port speeds from DS0 to | | | | the security offered by isolated paths. |
| DS3, multiple sites could be connected with a | | | | Advances in application based routing can |
| single port at each site. A partial or full | | | | achieve availablity assurances. Legacy |
| mesh, even with full redundancy, could be | | | | protocols have been largely replaced by |
| accomplished with very few router ports and | | | | IP.There are still times when frame relay is |
| CSU at each site. This represented | | | | the best choice based on business |
| significant capital savings.Using fractional | | | | requirements or technical constraints. But a |
| T1 and T3 on the access circuits, frame relay | | | | robust bandwidth network (e.g. OC3 or OC12 |
| made expanding capacity between sites | | | | bandwidth....perhaps with GigE connectivity) |
| relatively painless. Port changes within the | | | | applying IP protocols will enable a seemless |
| frame relay provider's network was often a | | | | flow of information without risking security |
| configuration change. Expanding the actual | | | | concerns.Emerging TechnologiesThe most |
| circuits was typically a configuration change | | | | notable is Radio Frequency Identification, or |
| on the CSU and DACS.Adding new sites was | | | | RFID. RFID tags are essentially barcodes on |
| often accomplished with physical changes at | | | | steroids. Whereas barcodes only identify the |
| the new site only. The new PVC across the | | | | product, RFID tags can tell what the product |
| frame relay network and at the existing | | | | is, where it has been, when it expires, |
| site(s) was a configuration change. Depending | | | | whatever information someone wishes to |
| on the routers used and the routing protocol | | | | program it with. RFID technology is going to |
| implemented, this might be accomplished | | | | generate mountains of data about the location |
| without a maintenance window.The PVC approach | | | | of pallets, cases, cartons, totes and |
| allowed for additional security. A given | | | | individual products in the supply chain. It's |
| location could be directed to a specific port | | | | going to produce oceans of information about |
| within the DMZ, limiting the exposure of | | | | when and where merchandise is manufactured, |
| one's own network to other vendors within the | | | | picked, packed and shipped. |