It thinks many companies could be affected, including equipment vendors Alcatel-Lucent (ALU -2.2%), Ciena (CIEN -3.9%), Juniper (JNPR +0.2%), and Adtran (ADTN -5.1%), and component vendors JDS Uniphase (JDSU -2%) and Finisar (FNSR -0.7%).
As its is, AT&T's 2014 capex budget ($21B) is down $200M from 2013's spending level. Moreover, the carrier's huge mobile infrastructure needs and the DirecTV deal could be motivating it to cut wireline spend.
Also: AT&T may be looking to keep capex down ahead of the full rollout of Domain 2.0, an initiative meant to improve network flexibility, lower costs, and cut provisioning times through the embrace of software-defined networking (SDN) and network functions virtualization (NFV).
MKM has argued Domain 2.0 will be a negative for Cisco, but a positive for Ciena and Finisar, among others.