As $subj may infer, do you guys follow any type of network lifecycle in your environment? If so - what would be some criteria you would consider critical: - consistent rate of cash flow, year after year, while replacing aging gear (allowing for consistent budgetary planning) - risk reduction while replacing unsupported equipment - security issues associated with OS or appliances not supported - business / apps demand for capacity or features (e.g. virtualization, SDN, etc.), laid out well in advance to allow for a 3-4-5 yrs plan with a consistent replacement rate of aging equipment - increased costs of support for aging equipment, or recertification for vendor support - anything else ... ??? Care to share some [other] aspects, as they may relate to $subj? Thanks, ***Stefan