Using a single vendor gives you an advantage because there are fewer products for which you need such equipment on hand. Since service contracts have recurring costs, evaluating whether your enterprise can maintain its own hot-spare program is particularly wise. Buying two identical products and putting one on the shelf is often more cost-effective. This makes going with a single-vendor solution especially intelligent, because it reduces the number of products you have sitting around on the shelf. Product service agreements are another important aspect of the single-vendor network.
Many vendors offer global access to all their support upgrades for one yearly fee.
This lets you upgrade code across the enterprise without paying multiple support fees to multiple vendors. For example, Enterasys offers all contract-support customers free access to switch code upgrades. Cisco's yearly maintenance fees gain you complete access to all downloadable software upgrades for Cisco equipment, though licensing arrangements vary. Extreme, Foundry and 3Com have similar programs in place. Likewise, with a single-vendor solution, upgrading does not require interoperability tests with each code upgrade.