Thus, IT leaders need to decide whether their ESN deployments will be all on premises, all in the cloud, or in a hydrid scenario, and then look into what the different vendors offer.
In the case of Microsoft, most SharePoint deployments to date have been on customer premises. However, the company has made it clear that the future of SharePoint and Office products in general is in the cloud via Office 365.
So Microsoft will support both models, but it is placing the development and innovation emphasis on the cloud-only Yammer and on SharePoint Online, the cloud version of the product that is part of the Office 365 cloud collaboration and communication suite.
It's not clear to what extent Microsoft will be able to maintain in sync SharePoint Online and SharePoint server, assuming SharePoint Online will be upgraded much more frequently and Yammer will remain cloud-only, Cannell said.
Koplowitz added: "If Yammer is the bet, then what about those folks who want SharePoint but can't go to the cloud?"
In light of those questions, CIOs who want to keep their SharePoint server on premises can rely on ESN add-ons like NewsGator's, which has been one of the preferred add-ons for years, and remains especially attractive for companies who aren't comfortable using SharePoint Online.
NewsGator's Social Sites is designed for SharePoint implementations on customer premises or in dedicated private clouds. Recently, the company has been working on extending Social Sites so that it will function not just as a SharePoint add on, but also play that part for other collaboration and business applications.
Other products offer cloud, on premises and hybrid deployment options, including IBM Connections, Jive and Tibbr, while vendors like Salesforce.com stick with a cloud-only approach with its Chatter product.
ESN Software May Be Used in Your Company Without Your Knowledge - and That Would Be Good
Some CIOs still pondering what ESN software to choose would be surprised to find out that employees have done an end-run around IT and adopted ESN tools already.
In fact, a lot of Yammer's adoption has happened in this way, as pockets of employees and managers sign up for the service and invite colleagues to join their network without consulting the IT department.
"See if a network already exists, find out who started it and learn how it's being used," Cannell says.
CIOs and IT managers on this quest should refrain from shutting down the networks they find.
"Don't look at this like a policy violation but as an opportunity to learn how you could use these tools," he said.
IT leaders should establish a relationship with these first adopters and build on their interest for ESN in order to get others enthused and eager to adopt ESN software.
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