Here is a list of major differences between the SA500 and SR500 series:
- The SA500 series and the SR520-T1 are considered Small Business Pro products, whereas the SR520-ADSL and SR520-FE are considered traditional Cisco products.
- The SA500 platform is non-IOS-based, whereas all of the current SR500 models, including the SR520-T1, are IOS-based.
- The SR520-ADSL and SR520-FE models are supported by the traditional TAC and SMARTnet service is offered on these models, whereas Small Business Pro services are offered on the SR520-T1 and SA500 series.
- SR520-ADSL, SR520-FE, and SR520-T1 models are designed to be CCA configurable, but have features that are not CCA configurable. The SR520-ADSL and SR520-FE models have advanced capabilities that are not available on the UC500 series or SA500 series (but are available on ISR platforms). On the other hand, the SA500 is not fully configurable in CCA yet (even though basic configuration of the SA500 was added to CCA 2.2.1 and later).
- The SA500 supports QuickVPN and SSL VPN, whereas the SR500 series supports Easy VPN, AnyConnect SSL VPN technology, and web-based SSL VPN.
- The SA500 supports ProtectLink Gateway, and the SR500 series does not support ProtectLink Gateway.
- The SR500 (along with the UC500 and ISR platforms) support routable IPsec VPN tunnel interfaces, whereas the SA500 does not support routable IPsec VPN tunnel interfaces. However, site-to-site VPNs are still supported on the SA500.
- SSL VPN on the SR520 series (and on ISR platforms) requires a separate SSL VPN license, whereas the SA520 ships with 2 SSL VPN client licenses (upgradeable to 25 SSL VPN licenses through a license upgrade) and the SA540 ships with 50 SSL VPN client licenses.
- The SR520-T1 is supported in CCA multisite manager, but the SR520-ADSL, SR520-FE, SA520, and SA540 are not yet supported in the CCA multisite manager.
- Whereas the SA500 platform has had known bugs and was unstable at the time of its release, the IOS-based SR520 platform tends to be more stable. There were even some early SA500 customers that were planning on trading in their SA500s for traditional Cisco products because of the bugs found in the SA500 firmware releases at the time of the SA500 release. The bugs on the UC500 platform tend to be in the unified communications components and not in data or security features.