While a shared channel path can be shared by LPARs within a same LCSS, a spanned  channel path can be shared by LPARs within and across LCSSs.  By assigning the same CHPID from different LCSSs to the same channel path (for example, a  PCHID), the channel path can be accessed by any LPARs from these LCSSs at the same  time. The CHPID is spanned across those LCSSs. The use of spanned channels paths  decreases the number of channels that are needed in an installation of Z servers. A sample of channel paths that are defined as dedicated, shared, and spanned is shown in  Figure 5-3. In the sample, the following definitions of a channel path are shown: Channel spanning is supported for internal links (HiperSockets and IC links) and for certain  types of external links. External links that are supported on z14 servers include FICON  Express16S+, FICON Express16S, FICON Express8S, OSA-Express6S, OSA-Express5S,  and Coupling Links.  The definition of LPAR name, MIF image ID, and LPAR ID are used to identify an LPAR by the  channel subsystem to identify I/O functions from different LPARs of multiple LCSSs, which  supports the implementation of these dedicated, shared, and spanned paths.  GLYPH<SM590000> CHPID FF, assigned to PCHID 20A is dedicated access for partition 15 of LCSS0. The  same applies to CHPID 00,01,02 of LCSS0, and CHPID 00,01,FF of LCSS1. GLYPH<SM590000> CHPID 03, assigned to PCHID 20E is shared access for partition 2, and 15 of LCSS0. The  same applies to CHPID 05 of LCSS1. GLYPH<SM590000> CHPID 06, assigned to PCHID 120 is spanned access for partition 1, 15 of LCSS0, and  partition 16, 17 of LCSS1. The same applies to CHPID 04. CSS0 Partition 1 . . . Partition 2 Partition 14 Partition 15 Partition 16 Partition 17 Partition 18 Partition 5A . . . MIF-1 MIF-2 MIF-F . . . CSS1 MIF-1 MIF-2 MIF-3 MIF-F CHPID 00 CHPID 01 CHPID 02 CHPID 03 Share PCHID 10B PCHID 10C PCHID 10D PCHID 20E . . . CHPID FF PCHID 20A CHPID 04 SPAN CHPID 06 SPAN PCHID 120 CHPID 00 CHPID 01 CHPID 05 Share CHPID 22 CHPID FF PCHID 145 PCHID 146 PCHID 147 PCHID 158 PCHID 159 . . . . . . . . . Figure 5-3 IBM Z CSS: Channel subsystems with channel spanning 202  IBM z14 (3906) Technical Guide