  The concept of a softwarized network leveraging technologies such as SDN and
NFV comes with different merits such as decreased Operational Expenses (OPEX)
and less dependency on underlying hardware components. With the amount of
increased flexibility, reconfigurability and programmability attributed to
future technologies (i.e. 5G and beyond), and towards the complete network
virtualization and softwarization, a new set of requirements or parameters can
be identified affecting the latency in a virtualized network. In this paper, we
identify different latency requirements for a virtualized network. These
requirements include the Virtual Network Function (VNF) deployment time,
establishment or connection time and application instantiation time. We further
test how some factors such as VNFs resource usage, the applications running
within the VNF and the shared status of the VNF, coordinately affect the
identified latency requirement for a virtualized network. Experimentally, for
performance analysis, we deploy a softwarized network based on the ETSI NFV
architecture, using open source tools. The results show that the new set of
latency requirements is relevant for consideration in order to achieve an
overall ultra reliable low latency and how different the factors can affect
these new requirements, especially in the core network. Furthermore, the result
of our performance analysis proves the trade off between latency of a
virtualized network and the resource usage of the VNFs
