Across seven key enterprise infrastructure segments vendor revenues for the last four quarters declined by 1% on an annualised basis, claims Synergy Research Group.
Aggregate revenues for the last four quarters reached $88bn, with revenue in each of the last 12 quarters typically in the $20-23bn range.
Data centre servers comprise the largest segment of the market though revenues here declined by almost 5% in 2016.
Switches and routers are the second largest segment and they experienced growth of 1%.
WLAN grew the most while the enterprise voice and telepresence markets continued to be challenged by aggressive price competition and market disruption.
According to Synergy Research Group, Cisco is the market leader in six of the seven segments with the exception being data centre servers, where it is ranked fifth.
In aggregate across the seven segments Cisco's market share over the last four quarters was 33%, in line with its share in the preceding four quarters.
HPE is the leader in data centre servers and is the number two ranked vendor in both switches and routers and WLAN.
Its aggregated market share over the four quarters was 16%. The number two ranked vendors in the other segments are Dell EMC (enterprise data center servers), Avaya (enterprise voice systems), Juniper (network security), Microsoft (UC applications) and Polycom (telepresence).
Vendors who have been achieving steady market share growth in these competitive markets include Palo Alto Networks (network security), Arista Networks (Ethernet switching), Huawei (Ethernet switching), HPE (WLAN) and Dell EMC (servers).
"Cisco continues to control a third of the enterprise infrastructure market and remains in a league of its own despite a variety of challenges," said Synergy Research Group's founder and Chief Analyst Jeremy Duke.
"HPE is the only broad-based competitor to challenge Cisco's dominance though it does not compete in all of the major segments.
"The main disruption to the market is being provided by the growth of cloud and hosted solutions, which are redefining markets and enabling new competitors to emerge."