OC3 lines carry a bandwidth of 155.5 Mbps. OC3 is the equivalent of three OC1s; each OC1 carries 51.85 Mbps. OC3 is great for facilitating Voice over IP, hosting web sites for very large companies, streaming audio and/or video, or video conferencing. OC3 carries enough bandwidth to supply most internet service providers. It is available in most major US cities. If a company does not need full OC3, other options include: burstable OC3 (pay only for what you use but have access to full OC3 for peak usage periods), fractional OC3, or OC1.