What are the strongest aspects of Lotus Domino?

I was asked recently to sum up the strongest points about Lotus Domino. This is what I came up with:

Lotus Domino is an integrated communication platform, that features email, instant messaging, collaboration and an application development platform. Its strongest points are self-containment, robustness, scalability, freedom of platform choice, security, extensibility, low cost of ownership and IBM's commitment.

Self-containment: Domino is not dependent on external applications other than the operating system and the network. While MS Exchange depends on Active Directory and Novell Groupwise on Novell's eDirectory, Domino provides it's own directory that also can serve as an LDAP directory for other applications. Due to the lack of external dependencies Domino servers can be moved from one platform to another with ease and low effort. More important: Running Domino does not require a bundle of different products and product skills. When comparing Domino's capabilities with Microsoft's offerings, you would need multiple Microsoft products to cover all Domino functionality: MS Active Directory, MS Exchange, MS Sharepoint, MS Life Connection Server and MS SQL.

Robustness: Domino uses individual databases for every mail user. The databases can synchronized ("replicated" in Notes lingo) between multiple servers and clients. Therefore Domino is very resilient against failures on one server or in one database. Combined with the active clustering and the choice of platforms a Domino system can be build with practical no perceivable downtime.

Scalability and platform choice: Domino is available on multiple platforms from Windows, Linux, Unix to z/OS. It provides cross-platform clustering and load balancing. An investment into a Domino cluster for high availability is paid back with better response times due to the load balancing functionality. IBM has provided benchmarks on notesbench.org where a single iSeries server supports 100,000 concurrent mail users.  However the most interesting aspect of the multi-platform availability is the possibility running Domino servers on different operating systems than the clients, thus providing a natural infection barrier for viruses and maleware. The platform choice doesn't stop with the servers. eMail and data stored in Domino can be accessed by a wealth of clients and protocols, giving the customer the freedom to pick the desktop (email) application of their choice: Lotus Notes Clients, IBM Workplace, MS Outlook, POP3/IMAP4 clients like Mozilla Thunderbird or web mail via a browser.

Security: Domino's granular access control to email, calendar and Domino applications is unique in the industry. Furthermore Domino provides digital signatures and encryption both in Domino's propriety format as well as the industry standard X509. Domino serves as the corporate PKI infrastructure, eliminating the need to invest into and introduce another technology for that. But there is more: Domino enables by design the lock-down of sensitive information, so even the system administrators could not retrieve it, so the data owners can be assured of data confidentiality.

Extensibility: Domino's mail design is completely open and can be customized to specific corporate needs. The OpenNTF open source community provides an free alternative to IBM's own design with enhanced functions putting pressure on IBM to constantly innovate. Besides eMail Domino features a platform for collaborative applications like discussion boards, blogs, wikis, CMS, CRM and a huge selection of open source or commercial applications. The latest version of Domino makes all this available as web services, in fact turning Domino into a pilar of a SOA strategy. Since the application share the platform with messaging they integrate well with email and allow the creation of an corporate unified information backbone.

Low cost of ownership and IBM's commitment: a well configured Domino platform takes advantage of the policy based administration, that minimizes administrative efforts through a set of comprehensive rules. In the latest release IBM also added a comprehensive domain monitoring capability. All this frees up valuable time for administrators to manage their environment more proactive. IBM is the single vendor with the most detailed roadmap for it's messaging platform. The current version Domino 7 has been released a few month ago, nevertheless IBM has outlined plans for Domino version 8 and 9. This assures users of the Domino platform, that they are not in for any rip and replace upgrade any time soon.