4.1 Introduction to I/O infrastructure 4.1.1 I/O infrastructure This section describes the I/O features that are available on the IBM z14 Model ZR1 server.  The z14 ZR1 servers support PCIe+ I/O drawers only. I/O cage, I/O drawer, or PCIe I/O  drawer are not supported. Note:  Throughout this chapter, the terms  adapter  and  card  refer to a PCIe I/O feature that  is installed in a PCIe+ I/O drawer. IBM extends the use of industry standards on the IBM Z platform by offering a Peripheral  Component Interconnect Express Generation 3 (PCIe Gen3) I/O infrastructure. The PCIe I/O  infrastructure that is provided by the central processor complex (CPC) improves I/O capability  and flexibility, while allowing for the future integration of PCIe adapters and accelerators. The PCIe I/O infrastructure in z14 ZR1 consists of the following components: The z14 ZR1 I/O infrastructure provides the following benefits:  GLYPH<SM590000> PCIe fanouts that support 16 GBps I/O bus for CPC drawer connectivity to the PCIe+ I/O  drawers.  GLYPH<SM590000> PCIe fanouts that support Coupling Link Feature Integrated Coupling Adapter Short  Reach (ICA SR). GLYPH<SM590000> The 8U, 16-slot, and 2-domain PCIe+ I/O drawer for PCIe I/O features. GLYPH<SM590000> The bus connecting the CPC drawer to the I/O domain in the PCIe+ I/O drawer bandwidth  is 16 GBps. GLYPH<SM590000> The PCIe+ I/O drawer also doubles the number of I/O ports compared to an I/O drawer  (z13s or earlier only). Up to 32 channels (16 PCIe I/O cards) are supported in the PCIe+  I/O drawer. GLYPH<SM590000> Granularity for the storage area network (SAN) and the local area network (LAN): – The FICON Express16S+ features two channels per feature for Fibre Channel  connection (FICON), High Performance FICON on Z (zHPF), and Fibre Channel  Protocol (FCP) storage area networks. – The Open Systems Adapter (OSA)-Exp ress6S GbE and the OSA-Express6S  1000BASE-T features includes two ports each (LAN connectivity); the OSA-Express7s  25GbE and the OSA-Express6S 10 GbE features have one port each (LAN  connectivity). GLYPH<SM590000> Native PCIe features (plugged into the PCIe+ I/O drawer): – IBM zHyperLink Express (new for z14 ZR1)  – 25GbE Remote Direct Memory Access (RDMA) over Converged Ethernet (RoCE)  Express2 (new) – 10 GbE RoCE Express2 (introduced with z14) – Coupling Express Long Reach (CE LR) (available on z14 M0x, z14 ZR1, z13, and  z13s) – zEnterprise Data Compression (zEDC) Express  – 10 GbE RDMA over RoCE Express (carry forward only) 118  IBM 14 Model ZR1 Technical Guide