Although VLSM, NAT, and other workarounds (for avoiding the transition to IPv6) are available, networks with internet connectivity must begin the transition to IPv6 as soon as possible. For IPv4 networks that provide goods and services to internet users, it is especially important because the transition by the internet community is already underway. New networks may be unable to acquire IPv4 addresses, and networks running IPv6 exclusively will not be able to communicate with IPv4-only networks unless you configure an intermediary gateway or another transition mechanism. IPv6 and IPv4 are completely separate protocols, and IPv6 is not backward compatible with IPv4. As the internet evolves, organizations must adopt IPv6 to support future business continuity, growth, and global expansion. Furthermore, some ISPs and Regional Internet Registries (RIRs) are administratively out of IPv4 addresses, meaning that their supply of IPv4 addresses is now limited, and organizations have to migrate to and support IPv6 networks.
雖然 VLSM、NAT 等其他因應措施（用以避免轉換至 IPv6）仍然存在，但具備網際網路連線能力的網路必須盡快開始轉換至 IPv6。對於向網際網路使用者提供商品與服務的 IPv4 網路而言，這一點格外重要，因為網際網路社群的轉換已在進行中。新建的網路可能無法取得 IPv4 位址，而完全執行 IPv6 的網路，除非設定中介閘道或其他轉換機制，否則將無法與僅使用 IPv4 的網路通訊。IPv6 與 IPv4 是完全獨立的協定，IPv6 並不向下相容於 IPv4。隨著網際網路持續演進，企業必須採用 IPv6，以支援未來的業務永續性、成長與全球擴展。此外，部分 ISP 與區域網際網路註冊管理機構（RIR）在行政上已無 IPv4 位址可分配，也就是說其 IPv4 位址供應量已經受限，企業必須轉移並支援 IPv6 網路。
IPv6 includes several features that make it attractive for building global-scale, highly effective networks:
IPv6 具備多項特性，使其非常適合用來建構全球規模、高效能的網路：
- Larger address space:The expanded address space includes several IP addressing enhancements:更大的位址空間：擴大的位址空間帶來多項 IP 定址上的強化：
- It provides improved global reachability and flexibility.提供更佳的全球可達性與彈性。
- A better aggregation of IP prefixes is announced in the routing tables. The aggregation of routing prefixes limits the number of routing table entries, creating efficient and scalable routing tables.在路由表中可宣告更佳的 IP 前綴聚合。路由前綴的聚合限制了路由表項目的數量，可建立高效且可擴充的路由表。
- Multihoming increases the reliability of the internet connection of an IP network. With IPv6, a host can have multiple IP addresses over one physical upstream link. For example, a host can connect to several ISPs.多重連接（multihoming）提升了 IP 網路網際網路連線的可靠性。透過 IPv6，一台主機可在單一實體上游連結上擁有多個 IP 位址，例如可連接到多個 ISP。
- Autoconfiguration is available.提供自動設定功能。
- There are more plug-and-play options for more devices.為更多裝置提供更多即插即用的選項。
- Simplified mechanisms are available for address renumbering and modification.提供簡化的位址重新編號與修改機制。
- Simpler header: Streamlined fixed header structures make the processing of IPv6 packets faster and more efficient for intermediate routers within the network. This fact is especially true when large numbers of packets are routed in the core of the IPv6 internet.更簡單的標頭：精簡的固定標頭結構，讓網路中間路由器處理 IPv6 封包更快速、更有效率。當網際網路核心需要路由大量封包時，這一點尤其重要。
- Security and mobility:Features that were not part of the original IPv4 specification, such as security and mobility, are now built into IPv6. IP Security (IPsec) is available in IPv6, allowing the IPv6 networks to be secure. Mobility enables mobile network devices to move around in networks without breaks in established network connections.安全性與行動性：原本不在 IPv4 規格中的功能，例如安全性與行動性，現已內建於 IPv6 中。IPv6 支援 IP 安全性（IPsec），使 IPv6 網路能夠保持安全。行動性則讓行動網路裝置能在網路間移動，而不會中斷既有的網路連線。
- Transition richness:IPv6 also includes a rich set of tools to aid in transitioning networks from IPv4, to allow an easy, nondisruptive transition over time to IPv6-dominant networks. An example is dual stacking, in which devices run both IPv4 and IPv6.豐富的轉換工具：IPv6 也包含一套豐富的工具，協助網路從 IPv4 轉換，讓網路能隨著時間逐步、無中斷地轉換至以 IPv6 為主的環境。其中一個範例是雙堆疊，即裝置同時執行 IPv4 與 IPv6。