5G core network

  5G core before deploying different communication protocols which can be used prior the EPC, may also be used 5GC, EPC Evolved packet core referred, plays a key role in the 4G LTE, 5GC is defined by 3GPP new 5G The core network. In addition to the above two, there 5GC standalone mode (SA), or EPC / non-independent mode (NSA) 5GC, increasing the complexity of the 5G looking for the best migration path.
  
  Supported between / 5GC LTE / EPC and NR redirection and inter-RAT handover, the problem can not be solved completely cover 5G service area, as shown:

  the 5G SA mode, and deployment 5GC gNodeB new network 5G independent (Option 2), with the deployment of LTE migration path similar to full capacity of 5G, only minor modifications to the existing EPC, can support interoperability with the 5G.
  

  The figure is deployed in the prior EPC gNodeB dependent 5G network (Option 3), which is applied NSA pattern has a dual connectivity, and NR provide LTE radio access while on the UE and the LTE supports NSA architecture. The advantage of this is that the migration path 5G early deployment does not require 5GC. Using the network design, control interface S1 is only to LTE eNodeB, and the S1 user plane interface may be provided to the eNodeB and NR gNodeB simultaneously. Therefore, in the EPC should classify traffic and divide.
  

  Introducing the non-independent migration path 5GC deployment, called Option 7, as shown above, Release-15 after evolution LTE (eLTE) eNodeB 5GC connected to the control and the new user interface, but only connected to 5GC gNodeB user interface. When deploying 5GC, upgrade to Option 7 2 provides better performance than SA Option. However, if the SA Option 2 deployment into the mainstream, then migrate to Option 7 it might not be necessary.
  

  The figure illustrates a deployment SA and NSA 5G NR (Option 2 and 4) across the country, the control plane is located in NR 5G, 5G provide adequate functionality to the user, is required NR 5G can provide continuous coverage. 5G NR deployment mature, gNodeB SA will replace the original deployment of LTE eNodeB (Option 2). In the NSA, Option 3 Option 7, and can be upgraded to Option 4, Option 4 also applicable to an LTE network architecture NSA double connection.
  
  From the beginning of 2017, NextEPC provides 4G LTE EPC open source software to promote private LTE network, and is expected to 5GC software solution implemented in mid-2020. The EPC and 5GC contained in a package in order to achieve a seamless transition from 5G 4G and dynamic service discovery honeycomb core service technology to promote distributed deployment; can achieve scalability and robustness.