Help wanted to connect Suns to IBM M/F

[Norman Hilton]

My employers run various kit (mainly Vaxen [Unix and VMS] and Suns)
interconnected by Ethernet. They now wish to access an IBM mainframe
(running VM/CMS) from some of this kit. There will probably be a need for
interactive working as well as file transfer and remote job entry.  I
believe there will be frequent access by a large number of users, so
products are required which are mature, supported and user-friendly.

Can anyone give me details of what hardware and software is available
for this? In particular:
  a) What hardware/software is available for making the ethernet/IBM
     connection and for any necessary protocol conversion?
  b) What software (or hardware?) is available for emulation
     of IBM terminals (presumably 3270s)? We have Sun workstations 
     and VT100 compatible terminals on Vaxen [Unix and VMS].

I would like some idea of cost, availability (in the UK), and support, and
need the names of companies and/or people to contact.  (If there are
technical problems, I would also appreciate information.)

(My appologies if this has been asked before, but I am new to this
newsgroup.)

Regards,
  Norman Hilton, STC Technology Ltd., London Rd., Harlow, England
  e-mail: normanh at stl.stc.co.uk  or  ...!mcvax!ukc!stl!normanh
  phone:  +44-279-29531 x3657