Exchange 2010 Enterprise Architecture – UNC316

A. key highlights:
1. still the same 5 role
2. all clients OWA/Outlook connect only to CAS server now
3. CAS server is the single end point for mailbox clients:
a. CAS removes DSPROXY by providing address service: CAS Array
b. RPC client access service :( only mailboxes on 2010 will follow this)
c. simplifies AD topology requirement for outlook
d. supports more concurrent connection to outlook

4. failover switch level on database level not servers level
5. 30 sec failover instead of 2-3 min as experienced on exchange 2007

B. Outlook anywhere and CAS:
1. In 2007 Two connections established: rpc in data and rpc out data. Having two sessions open with integration of SSL-ID was an issue. This would require two id’s. This created problems for profiles and killing sessions.

2. Use of the CAS array on 2010 fixes the two connection issue since CAS server does the dsproxy.
3. CAS servers are now the client (outlook, owa, active sync) end points providing not only RPC requests but also directory lookup
4. 2010 CAS servers will require more beefy hardware requirement due to additional roles

C. Writing to the directory: i.e., users updating a DL membership
1. CAS array now has nspi end point. Users make requests/changes. The change is pushed to GAL on backend via power shell

D. Better Scaling of mailbox connection:
1. windows 2008, allows for reuse of source ports for outbound CAS connection
2. Store process limited to 60k rpc connection on 2007 ~15k mailbox connection. With 2010, RPC end point/NSPI endpoint being on CAS:
a. RPC connection pools on CAS, 100k
b. RPC connection can be reutilized on CAS
c. recommended ISA:CAS ration 3:1.(for100% outlook anywhere) limitation here is ISA (32 bit) limited TCP connection per IS

E. Architectural consideration:
1. mixed mode deployment: as long as you have 2007 mailbox, you will need 2007 CAS server. users on 2007 mailboxes will utilize 2007 CAS and Hub servers for connection and transport where as 2010 users will only use 2010 HUB and CAS servers for delivery and connection. Delivery between version be handled by hub servers of both servers.
2. load balancing: for more than 8 CAS servers, consider Hardware load balancing

F. Exchange Transport: 2010 still uses JET but the following changes collectively results in reduced IO requirement
1. 2010 still uses JET.
2. ESE Page size went from 8K (2007) to 32K
3. ESE database page compression
4. Intrinsic long value record storage: on 2007 a typical message would require 13 IO. With Intrinsic long value record storage less page file is required per message
5. Increase in DB cache size to 1 GB
6. Check point depth increases from 128Mb to 512Mb
7. ESE version store maintenance

G. Transport server: shadow redundancy
1. Transport server keeps a copy of message locally while in transit.
a. Xshadow: hub retains copy in xshadow
b. xqdiscard: hub queries edge and once confirmed discards a local copy. By default every 5 min connection is made to edge to confirm delivery
c. once 3 request has been made and no response, hub sends message to edge2. What about duplicates? No guarantee that there is a duplicate detection for a non exchange external mail host but hotmail and gmail are able to detect

H. dumpster changes
1. db replication feedback is now used to control which messages remains in dumpster
2. when message has been relocated to all db copies message is truncated from dumpster
3. dumpster size is based on replication

I. Edge Server:
1. Better ADAM sync: with 2007 Edge syncs involved full rewrite of ADAM. With 2010 only deltas are synced since the last synchronization using cookie hash algorithm
2. Better SPAM filter: with 2007 only safe sender list was synchronized from client to edge. With 2010 safe senders, block list, and safe recipients are synchronized as well. 2010 also gives configurable safe list Quota and automatic safe sender update.

J. Mailbox Server:
1. Clients no longer make RPC connections to mailbox server
2. Store Schema changes allows for 100k items in mailbox from 20k (2007)
3. 30 sec failover: exchange no longer fails over entire exchange server. the new exchange is more database centric so failover is now a exchange task that involves database.
4. Public folders: still there in 2010, does not leverage CCR

K. UM:
1. Still recommend using physical stand alone server
2. Message preview with speech to text: this feature brings on additional overhead. Recommended memory is 8GB
3. Message preview is part of the message body so this can be searched against on a mailbox level and also across many mailboxes (E-Discovery). We should be able to search within EX as

L. Other improvements:
1. 2010 gives ability to measure message delivery and latency. You can now locate bottle neck in the message path and measure against set SLA
2. ISA will be split into 2 products: unfired access gateway and threat management gateway – both will be 64bit