10.4 Remote Support Facility 10.4.1 Security characteristics 10.4.2 RSF connections to IBM and Enhanced IBM Service Support System The HMC Remote Support Facility (RSF) provides important communication to a centralized  IBM support network for hardware problem reporting and service. The following types of  communication are provided: Consideration:  RSF through a modem is  not  supported on the z15 HMC. Broadband  connectivity is needed for hardware problem reporting and service.  The following security characteristics are in effect: More information:  For more information about the benefits of Broadband RSF and the  SSL/TLS-secured protocol, and a sample configuration for the Broadband RSF  connection, see Integrating the HMC Broadband Remote Support Facility into Your  Enterprise , SC28-6986. If the HMC and SE are at Driver 22 or later, the driver uses a new remote infrastructure at IBM  when the HMC connects through RSF for certain tasks. Check your network infrastructure  settings to ensure that this new infrastructure works. At the time of this writing, RSF still uses the “traditional” RETAIN co nnection. You must add  access to the new Enhanced IBM Service Support System to your current RSF infrastructure  (proxy, firewall, and so on). To have the best availability and redundancy and to be prepared for the future, the HMC must  access IBM by using the internet through RSF in the following manner: Transmission to the  enhanced IBM Support System requires a domain name server (DNS). The DNS must be  configured on the HMC if a proxy for RSF is not used. If a proxy for RSF is used, the proxy  must provide the DNS. The following host names and IP addresses are used and your network infrastructure must  allow the HMC to access the following host names: GLYPH<SM590000> Problem reporting and repair data GLYPH<SM590000> Microcode Change Level (MCL) delivery GLYPH<SM590000> Hardware inventory data, which is also known as vital product data (VPD) GLYPH<SM590000> On-demand enablement GLYPH<SM590000> RSF requests always are started from the HMC to IBM. An inbound connection is never  started from the IBM Service Support System. GLYPH<SM590000> All data that is transferred between the HMC and the IBM Service Support System is  encrypted with high-grade SSL/Transport Layer Security (TLS) encryption. GLYPH<SM590000> When starting the SSL/TLS-encrypted connection, the HMC validates the trusted host  with the digital signature that is issued for the IBM Service Support System.  GLYPH<SM590000> Data that is sent to the IBM Service Support System consists of hardware problems and  configuration data. GLYPH<SM590000> www-945.ibm.com on port 443  GLYPH<SM590000> esupport.ibm.com on port 443  Chapter 10. Hardware Management Console and Support Element  427