Sprint gives frame relay new priorities

     Kansas City, Mo.
     Sprint Corp. last week revamped its frame relay service, putting 
class-of-service performance guarantees front and center.
     The carrier divided its flagship fast-packet offering into three 
classes of service: LAN-to-LAN interconnection, SNA over frame relay and 
voice over frame relay. Utilizing separate permanent virtual circuits 
(PVC), the LAN and SNA services are available immediately. The voice 
service is slated for introduction early next year.
     Analysts said Sprint's action is the most significant development so 
far in the movement to bring quality of service (QoS) guarantees to frame 
relay. Carriers are using enhancements on their frame relay switches to 
identify and give priority to SNA, voice and other time-sensitive traffic 
(NW, Jan. 20, page 1).
     MCI Communications Corp. earlier this year gave users the option of 
assigning a high, medium or low priority to their PVCs. But analysts and 
MCI officials last week said MCI's Priority PVC option merely instructs 
MCI's Bay Networks, Inc. switches to allow some portion of an individual 
user company's traffic - such as keystrokes in an SNA terminal-to-host 
session - to ride the network first while holding the same user's file 
transfer and e-mail traffic in a buffer.
     By contrast, Sprint is employing a variety of prioritization 
techniques to guarantee that the traffic of all users of the new Frame 
Relay for SNA service transits the Sprint network in a maximum of 50 msec. 
Sprint set the maximum latency of the new Frame Relay for LAN service at 65 
msec.
     Sprint also introduced end-to-end latency guarantees covering the 
Sprint network and local carriers' access and termination circuits. The 
end-to-end network delay is lowest for users with a high-capacity access 
circuit such as a T-1, but SNA traffic gets priority at any givenaccess 
speed (see graphic).
     Sprint's experience working with local carriers enables it to predict 
their carriers' performance levels and take a chance on an end-to-end 
guarantee, said Brad Hokamp, Sprint's vice president for data product 
management. 
     The new Sprint services use the prioritization features of its 38 new 
Magellan Passport switches from Northern Telecom, Inc. Running in a 
parallel network with Sprint's older frame relay switches from Alcatel Data 
Networks, Inc., the Passports take in traffic via a frame relay 
user-to-network interface and ship it across the Sprint network via ATM 
cells. ATM offers standard QoS classes, while frame relay does not, Hokamp 
noted. Users who order the LAN and SNA service will receive ports on the 
Nortel switches.
     'What this basically says is that new customers go on this new 
network,' said Christine Heckart, senior broadband consultant for 
TeleChoice, Inc., a consulting firm based in Verona, N.J.  Already 70% of 
frame relay users ship some SNA traffic on their fast-packet nets, she 
said, despite frame relay's roots handling LAN interconnection protocols 
such as IPX and IP.
     Users may have to reassess their budgets to take advantage of Sprint's 
new offerings. Those with multiprotocol traffic will have to purchase dual 
PVCs out of each network node, one for LAN traffic and one for SNA traffic. 
To ease that burden, Sprint lowered its traditionally high PVC prices, 
though it also instituted a large price differential between the LAN and 
SNA PVCs.
     For example, Sprint had been charging $140 a month for any PVC with a 
committed information rate - or rate at which frames cannot be discarded - 
of 16K bit/sec. Now the same PVCs cost $44 a month for LAN interconnection 
traffic and $68 a month for SNA traffic. At the same time, Sprint raised 
its frame relay port charges across the board by 14% to 20%, in line with a 
recent industry trend.
     The only additional fee for ordering MCI's Priority PVC service is a 
onetime $20 charge per PVC to set up the service. The net impact is that 
Sprint's frame relay prices remain about 15% higher than MCI's, officials 
with both carriers agreed.